1
|
Ahluwalia K, Du Z, Martinez-Camarillo JC, Naik A, Thomas BB, Pollalis D, Lee SY, Dave P, Zhou E, Li Z, Chester C, Humayun MS, Louie SG. Unveiling Drivers of Retinal Degeneration in RCS Rats: Functional, Morphological, and Molecular Insights. Int J Mol Sci 2024; 25:3749. [PMID: 38612560 PMCID: PMC11011632 DOI: 10.3390/ijms25073749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Revised: 03/12/2024] [Accepted: 03/22/2024] [Indexed: 04/14/2024] Open
Abstract
Retinal degenerative diseases, including age-related macular degeneration and retinitis pigmentosa, significantly contribute to adult blindness. The Royal College of Surgeons (RCS) rat is a well-established disease model for studying these dystrophies; however, molecular investigations remain limited. We conducted a comprehensive analysis of retinal degeneration in RCS rats, including an immunodeficient RCS (iRCS) sub-strain, using ocular coherence tomography, electroretinography, histology, and molecular dissection using transcriptomics and immunofluorescence. No significant differences in retinal degeneration progression were observed between the iRCS and immunocompetent RCS rats, suggesting a minimal role of adaptive immune responses in disease. Transcriptomic alterations were primarily in inflammatory signaling pathways, characterized by the strong upregulation of Tnfa, an inflammatory signaling molecule, and Nox1, a contributor to reactive oxygen species (ROS) generation. Additionally, a notable decrease in Alox15 expression was observed, pointing to a possible reduction in anti-inflammatory and pro-resolving lipid mediators. These findings were corroborated by immunostaining, which demonstrated increased photoreceptor lipid peroxidation (4HNE) and photoreceptor citrullination (CitH3) during retinal degeneration. Our work enhances the understanding of molecular changes associated with retinal degeneration in RCS rats and offers potential therapeutic targets within inflammatory and oxidative stress pathways for confirmatory research and development.
Collapse
Affiliation(s)
- Kabir Ahluwalia
- Mann School of Pharmacy and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA 90089, USA; (K.A.); (A.N.); (P.D.); (E.Z.); (Z.L.); (C.C.)
| | - Zhaodong Du
- USC Ginsburg Institute of for Biomedical Therapeutics, University of Southern California, Los Angeles, CA 90033, USA; (Z.D.); (J.C.M.-C.); (B.B.T.); (D.P.); (S.Y.L.); (M.S.H.)
| | - Juan Carlos Martinez-Camarillo
- USC Ginsburg Institute of for Biomedical Therapeutics, University of Southern California, Los Angeles, CA 90033, USA; (Z.D.); (J.C.M.-C.); (B.B.T.); (D.P.); (S.Y.L.); (M.S.H.)
- Roski Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Aditya Naik
- Mann School of Pharmacy and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA 90089, USA; (K.A.); (A.N.); (P.D.); (E.Z.); (Z.L.); (C.C.)
| | - Biju B. Thomas
- USC Ginsburg Institute of for Biomedical Therapeutics, University of Southern California, Los Angeles, CA 90033, USA; (Z.D.); (J.C.M.-C.); (B.B.T.); (D.P.); (S.Y.L.); (M.S.H.)
- Roski Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Dimitrios Pollalis
- USC Ginsburg Institute of for Biomedical Therapeutics, University of Southern California, Los Angeles, CA 90033, USA; (Z.D.); (J.C.M.-C.); (B.B.T.); (D.P.); (S.Y.L.); (M.S.H.)
- Roski Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Sun Young Lee
- USC Ginsburg Institute of for Biomedical Therapeutics, University of Southern California, Los Angeles, CA 90033, USA; (Z.D.); (J.C.M.-C.); (B.B.T.); (D.P.); (S.Y.L.); (M.S.H.)
- Roski Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
- Department of Physiology & Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA
| | - Priyal Dave
- Mann School of Pharmacy and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA 90089, USA; (K.A.); (A.N.); (P.D.); (E.Z.); (Z.L.); (C.C.)
| | - Eugene Zhou
- Mann School of Pharmacy and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA 90089, USA; (K.A.); (A.N.); (P.D.); (E.Z.); (Z.L.); (C.C.)
| | - Zeyang Li
- Mann School of Pharmacy and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA 90089, USA; (K.A.); (A.N.); (P.D.); (E.Z.); (Z.L.); (C.C.)
| | - Catherine Chester
- Mann School of Pharmacy and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA 90089, USA; (K.A.); (A.N.); (P.D.); (E.Z.); (Z.L.); (C.C.)
| | - Mark S. Humayun
- USC Ginsburg Institute of for Biomedical Therapeutics, University of Southern California, Los Angeles, CA 90033, USA; (Z.D.); (J.C.M.-C.); (B.B.T.); (D.P.); (S.Y.L.); (M.S.H.)
- Roski Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Stan G. Louie
- Mann School of Pharmacy and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA 90089, USA; (K.A.); (A.N.); (P.D.); (E.Z.); (Z.L.); (C.C.)
- USC Ginsburg Institute of for Biomedical Therapeutics, University of Southern California, Los Angeles, CA 90033, USA; (Z.D.); (J.C.M.-C.); (B.B.T.); (D.P.); (S.Y.L.); (M.S.H.)
| |
Collapse
|
2
|
Lu B, Avalos P, Svendsen S, Zhang C, Nocito L, Jones MK, Pieplow C, Saylor J, Ghiam S, Block A, Fernandez M, Ljubimov AV, Small K, Liao D, Svendsen CN, Wang S. GMP-grade human neural progenitors delivered subretinally protect vision in rat model of retinal degeneration and survive in minipigs. J Transl Med 2023; 21:650. [PMID: 37743503 PMCID: PMC10519102 DOI: 10.1186/s12967-023-04501-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 09/02/2023] [Indexed: 09/26/2023] Open
Abstract
BACKGROUND Stem cell products are increasingly entering early stage clinical trials for treating retinal degeneration. The field is learning from experience about comparability of cells proposed for preclinical and clinical use. Without this, preclinical data supporting translation to a clinical study might not adequately reflect the performance of subsequent clinical-grade cells in patients. METHODS Research-grade human neural progenitor cells (hNPC) and clinical-grade hNPC (termed CNS10-NPC) were injected into the subretinal space of the Royal College of Surgeons (RCS) rat, a rodent model of retinal degeneration such as retinitis pigmentosa. An investigational new drug (IND)-enabling study with CNS10-NPC was performed in the same rodent model. Finally, surgical methodology for subretinal cell delivery in the clinic was optimized in a large animal model with Yucatan minipigs. RESULTS Both research-grade hNPC and clinical-grade hNPC can survive and provide functional and morphological protection in a dose-dependent fashion in RCS rats and the optimal cell dose was defined and used in IND-enabling studies. Grafted CNS10-NPC migrated from the injection site without differentiation into retinal cell phenotypes. Additionally, CNS10-NPC showed long-term survival, safety and efficacy in a good laboratory practice (GLP) toxicity and tumorigenicity study, with no observed cell overgrowth even at the maximum deliverable dose. Finally, using a large animal model with the Yucatan minipig, which has an eye size comparable to the human, we optimized the surgical methodology for subretinal cell delivery in the clinic. CONCLUSIONS These extensive studies supported an approved IND and the translation of CNS10-NPC to an ongoing Phase 1/2a clinical trial (NCT04284293) for the treatment of retinitis pigmentosa.
Collapse
Affiliation(s)
- Bin Lu
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, 90048, USA
| | - Pablo Avalos
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, 90048, USA
| | - Soshana Svendsen
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, 90048, USA
| | - Changqing Zhang
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, 90048, USA
| | - Laura Nocito
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, 90048, USA
| | - Melissa K Jones
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, 90048, USA
| | - Cosmo Pieplow
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, 90048, USA
| | - Joshua Saylor
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, 90048, USA
| | - Sean Ghiam
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, 90048, USA
| | - Amanda Block
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, 90048, USA
| | - Michael Fernandez
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, 90048, USA
| | - Alexander V Ljubimov
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, 90048, USA
- David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, 90095, USA
| | - Kent Small
- Macula& Retina Institute, Glendale, CA, 91203, USA
| | - David Liao
- Retina Vitreous Associates Medical Group, Beverly Hills, CA, 90211, USA
| | - Clive N Svendsen
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, 90048, USA.
- David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, 90095, USA.
| | - Shaomei Wang
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, 90048, USA.
- David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, 90095, USA.
| |
Collapse
|
3
|
Laperle AH, Moser VA, Avalos P, Lu B, Wu A, Fulton A, Ramirez S, Garcia VJ, Bell S, Ho R, Lawless G, Roxas K, Shahin S, Shelest O, Svendsen S, Wang S, Svendsen CN. Human iPSC-derived neural progenitor cells secreting GDNF provide protection in rodent models of ALS and retinal degeneration. Stem Cell Reports 2023; 18:1629-1642. [PMID: 37084724 PMCID: PMC10444557 DOI: 10.1016/j.stemcr.2023.03.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 03/24/2023] [Accepted: 03/27/2023] [Indexed: 04/23/2023] Open
Abstract
Human induced pluripotent stem cells (iPSCs) are a renewable cell source that can be differentiated into neural progenitor cells (iNPCs) and transduced with glial cell line-derived neurotrophic factor (iNPC-GDNFs). The goal of the current study is to characterize iNPC-GDNFs and test their therapeutic potential and safety. Single-nuclei RNA-seq show iNPC-GDNFs express NPC markers. iNPC-GDNFs delivered into the subretinal space of the Royal College of Surgeons rodent model of retinal degeneration preserve photoreceptors and visual function. Additionally, iNPC-GDNF transplants in the spinal cord of SOD1G93A amyotrophic lateral sclerosis (ALS) rats preserve motor neurons. Finally, iNPC-GDNF transplants in the spinal cord of athymic nude rats survive and produce GDNF for 9 months, with no signs of tumor formation or continual cell proliferation. iNPC-GDNFs survive long-term, are safe, and provide neuroprotection in models of both retinal degeneration and ALS, indicating their potential as a combined cell and gene therapy for various neurodegenerative diseases.
Collapse
Affiliation(s)
- Alexander H Laperle
- Cedars-Sinai Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - V Alexandra Moser
- Cedars-Sinai Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Pablo Avalos
- Cedars-Sinai Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Bin Lu
- Cedars-Sinai Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Amanda Wu
- Cedars-Sinai Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Aaron Fulton
- Cedars-Sinai Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Stephany Ramirez
- Cedars-Sinai Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Veronica J Garcia
- Cedars-Sinai Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Shaughn Bell
- Cedars-Sinai Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Ritchie Ho
- Cedars-Sinai Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - George Lawless
- Cedars-Sinai Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Kristina Roxas
- Cedars-Sinai Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Saba Shahin
- Cedars-Sinai Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Oksana Shelest
- Cedars-Sinai Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Soshana Svendsen
- Cedars-Sinai Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Shaomei Wang
- Cedars-Sinai Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
| | - Clive N Svendsen
- Cedars-Sinai Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
| |
Collapse
|
4
|
Transplantation of human neural progenitor cells secreting GDNF into the spinal cord of patients with ALS: a phase 1/2a trial. Nat Med 2022; 28:1813-1822. [PMID: 36064599 PMCID: PMC9499868 DOI: 10.1038/s41591-022-01956-3] [Citation(s) in RCA: 42] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Accepted: 07/18/2022] [Indexed: 11/08/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) involves progressive motor neuron loss, leading to paralysis and death typically within 3–5 years of diagnosis. Dysfunctional astrocytes may contribute to disease and glial cell line-derived neurotrophic factor (GDNF) can be protective. Here we show that human neural progenitor cells transduced with GDNF (CNS10-NPC-GDNF) differentiated to astrocytes protected spinal motor neurons and were safe in animal models. CNS10-NPC-GDNF were transplanted unilaterally into the lumbar spinal cord of 18 ALS participants in a phase 1/2a study (NCT02943850). The primary endpoint of safety at 1 year was met, with no negative effect of the transplant on motor function in the treated leg compared with the untreated leg. Tissue analysis of 13 participants who died of disease progression showed graft survival and GDNF production. Benign neuromas near delivery sites were common incidental findings at post-mortem. This study shows that one administration of engineered neural progenitors can provide new support cells and GDNF delivery to the ALS patient spinal cord for up to 42 months post-transplantation. A phase 1/2a study shows that human neural progenitor cells modified to release the growth factor GDNF are safely transplanted into the spinal cord of patients with ALS, with cell survival and GDNF production for over 3 years.
Collapse
|
5
|
Stem cell transplantation as a progressing treatment for retinitis pigmentosa. Cell Tissue Res 2022; 387:177-205. [PMID: 35001210 DOI: 10.1007/s00441-021-03551-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 10/27/2021] [Indexed: 11/02/2022]
Abstract
Retinal degenerative diseases such as retinitis pigmentosa (RP) are of the major causes of vision loss in developed countries. Despite the unclear pathophysiology, treatment methods have been investigated vastly in the past decades. This review article mainly discusses the advances in application of stem cell and progenitor transplantation for retinitis pigmentosa. Stem cell sources such as mesenchymal stem cells, embryonic stem cells, induced pluripotent stem cells, neural stem cells, retinal progenitor cells, and olfactory ensheathing cells are discussed separately in addition to a brief description of two approaches for treatment of early-stage RP, including gene therapy and nutritional therapy.
Collapse
|
6
|
Chen M, Ren C, Ren B, Fang Y, Li Q, Zeng Y, Li Y, Chen F, Bian B, Liu Y. Human Retinal Progenitor Cells Derived Small Extracellular Vesicles Delay Retinal Degeneration: A Paradigm for Cell-free Therapy. Front Pharmacol 2021; 12:748956. [PMID: 34912217 PMCID: PMC8667779 DOI: 10.3389/fphar.2021.748956] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 11/02/2021] [Indexed: 01/03/2023] Open
Abstract
Retinal degeneration is a leading cause of irreversible vision impairment and blindness worldwide. Previous studies indicate that subretinal injection of human retinal progenitor cells (hRPCs) can delay the progression of retinal degeneration, preserve retinal function, and protect photoreceptor cells from death, albeit the mechanism is not well understood. In this study, small extracellular vesicles derived from hRPCs (hRPC-sEVs) were injected into the subretinal space of retinal dystrophic RCS rats. We find that hRPC-sEVs significantly preserve the function of retina and thickness of the outer nuclear layer (ONL), reduce the apoptosis of photoreceptors in the ONL, and suppress the inflammatory response in the retina of RCS rats. In vitro, we have shown that hRPC-sEV treatment could significantly reserve the low-glucose preconditioned apoptosis of photoreceptors and reduce the expression of pro-inflammatory cytokines in microglia. Pathway analysis predicted the target genes of hRPC-sEV microRNAs involved in inflammation related biological processes and significantly enriched in processes autophagy, signal release, regulation of neuron death, and cell cycle. Collectively, our study suggests that hRPC-sEVs might be a favorable agent to delay retinal degeneration and highlights as a new paradigm for cell-free therapy.
Collapse
Affiliation(s)
- Min Chen
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, China.,Key Lab of Visual Damage and Regeneration and Restoration of Chongqing, Chongqing, China
| | - Chunge Ren
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, China.,Key Lab of Visual Damage and Regeneration and Restoration of Chongqing, Chongqing, China
| | - Bangqi Ren
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, China.,Key Lab of Visual Damage and Regeneration and Restoration of Chongqing, Chongqing, China
| | - Yajie Fang
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, China.,Key Lab of Visual Damage and Regeneration and Restoration of Chongqing, Chongqing, China
| | - Qiyou Li
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, China.,Key Lab of Visual Damage and Regeneration and Restoration of Chongqing, Chongqing, China
| | - Yuxiao Zeng
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, China.,Key Lab of Visual Damage and Regeneration and Restoration of Chongqing, Chongqing, China
| | - Yijian Li
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, China.,Key Lab of Visual Damage and Regeneration and Restoration of Chongqing, Chongqing, China
| | - Fang Chen
- Department of Medical Technology, Chongqing Medical and Pharmaceutical College, Chongqing, China
| | - Baishijiao Bian
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, China.,Key Lab of Visual Damage and Regeneration and Restoration of Chongqing, Chongqing, China.,Army 953 Hospital, Shigatse Branch of Xinqiao Hospital, Army Medical University, Shigatse, China
| | - Yong Liu
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, China.,Key Lab of Visual Damage and Regeneration and Restoration of Chongqing, Chongqing, China
| |
Collapse
|
7
|
Caras IW, Collins LR, Creasey AA. A stem cell JOURNEY IN OPHTHALMOLOGY: From the bench to the clinic. Stem Cells Transl Med 2021; 10:1581-1587. [PMID: 34515419 PMCID: PMC8641078 DOI: 10.1002/sctm.21-0239] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 08/05/2021] [Accepted: 08/21/2021] [Indexed: 01/10/2023] Open
Abstract
Debilitating diseases of the eye represent a large unmet medical need potentially addressable with stem cell-based approaches. Over the past decade, the California Institute for Regenerative Medicine (CIRM) has funded and supported the translation, from early research concepts to human trials, of therapeutic stem cell approaches for dry age-related macular degeneration, retinitis pigmentosa, and limbal stem cell deficiency. This article chronicles CIRM's journey in the ophthalmology field and discusses some key challenges and questions that were addressed along the way as well as questions that remain.
Collapse
Affiliation(s)
- Ingrid W Caras
- The California Institute for Regenerative Medicine, Oakland, California, USA
| | - Lila R Collins
- The California Institute for Regenerative Medicine, Oakland, California, USA
| | - Abla A Creasey
- The California Institute for Regenerative Medicine, Oakland, California, USA
| |
Collapse
|
8
|
Rohiwal SS, Ellederová Z, Ardan T, Klima J. Advancement in Nanostructure-Based Tissue-Engineered Biomaterials for Retinal Degenerative Diseases. Biomedicines 2021; 9:biomedicines9081005. [PMID: 34440209 PMCID: PMC8393745 DOI: 10.3390/biomedicines9081005] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 08/07/2021] [Accepted: 08/10/2021] [Indexed: 12/20/2022] Open
Abstract
The review intends to overview a wide range of nanostructured natural, synthetic and biological membrane implants for tissue engineering to help in retinal degenerative diseases. Herein, we discuss the transplantation strategies and the new development of material in combination with cells such as induced pluripotent stem cells (iPSC), mature retinal cells, adult stem cells, retinal progenitors, fetal retinal cells, or retinal pigment epithelial (RPE) sheets, etc. to be delivered into the subretinal space. Retinitis pigmentosa and age-related macular degeneration (AMD) are the most common retinal diseases resulting in vision impairment or blindness by permanent loss in photoreceptor cells. Currently, there are no therapies that can repair permanent vision loss, and the available treatments can only delay the advancement of retinal degeneration. The delivery of cell-based nanostructure scaffolds has been presented to enrich cell survival and direct cell differentiation in a range of retinal degenerative models. In this review, we sum up the research findings on different types of nanostructure scaffolds/substrate or material-based implants, with or without cells, used to deliver into the subretinal space for retinal diseases. Though, clinical and pre-clinical trials are still needed for these transplants to be used as a clinical treatment method for retinal degeneration.
Collapse
|
9
|
Ludwig AL, Gamm DM. Outer Retinal Cell Replacement: Putting the Pieces Together. Transl Vis Sci Technol 2021; 10:15. [PMID: 34724034 PMCID: PMC8572485 DOI: 10.1167/tvst.10.10.15] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 09/09/2021] [Indexed: 12/17/2022] Open
Abstract
Retinal degenerative diseases (RDDs) affecting photoreceptors (PRs) are one of the most prevalent sources of incurable blindness worldwide. Due to a lack of endogenous repair mechanisms, functional cell replacement of PRs and/or retinal pigmented epithelium (RPE) cells are among the most anticipated approaches for restoring vision in advanced RDD. Human pluripotent stem cell (hPSC) technologies have accelerated development of outer retinal cell therapies as they provide a theoretically unlimited source of donor cells. Human PSC-RPE replacement therapies have progressed rapidly, with several completed and ongoing clinical trials. Although potentially more promising, hPSC-PR replacement therapies are still in their infancy. A first-in-human trial of hPSC-derived neuroretinal transplantation has recently begun, but a number of questions regarding survival, reproducibility, functional integration, and mechanism of action remain. The discovery of biomaterial transfer between donor and PR cells has highlighted the need for rigorous safety and efficacy studies of PR replacement. In this review, we briefly discuss the history of neuroretinal and PR cell transplantation to identify remaining challenges and outline a stepwise approach to address specific pieces of the outer retinal cell replacement puzzle.
Collapse
Affiliation(s)
- Allison L. Ludwig
- Waisman Center, University of Wisconsin–Madison, Madison, WI, USA
- McPherson Eye Research Institute, University of Wisconsin–Madison, Madison, WI, USA
- School of Veterinary Medicine, University of Wisconsin–Madison, Madison, WI, USA
| | - David M. Gamm
- Waisman Center, University of Wisconsin–Madison, Madison, WI, USA
- McPherson Eye Research Institute, University of Wisconsin–Madison, Madison, WI, USA
- Department of Ophthalmology and Visual Sciences, University of Wisconsin–Madison, Madison, WI, USA
| |
Collapse
|
10
|
Goel M, Dhingra NK. bFGF and insulin lead to migration of Müller glia to photoreceptor layer in rd1 mouse retina. Neurosci Lett 2021; 755:135936. [PMID: 33910061 DOI: 10.1016/j.neulet.2021.135936] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Accepted: 04/23/2021] [Indexed: 10/21/2022]
Abstract
Müller glia can act as endogenous stem cells and regenerate the missing neurons in the injured or degenerating retina in lower vertebrates. However, mammalian Müller glia, although can sometimes express stem cell markers and specific neuronal proteins in response to injury or degeneration, do not differentiate into functional neurons. We asked whether bFGF and insulin would stimulate the Müller glia to migrate, proliferate and differentiate into photoreceptors in rd1 mouse. We administered single or repeated (two or three) intravitreal injections of basic fibroblast growth factor (bFGF;200 μg) and insulin (2 μg) in 2-week-old rd1 mice. Müller glia were checked for proliferation, migration and differentiation using immunostaining. A single injection resulted within 5 days in a decrease in the numbers of Müller glia in the inner nuclear layer (INL) and a corresponding increase in the outer nuclear layer (ONL). The total number of Müller glia in the INL and ONL was unaltered, suggesting that they did not proliferate, but migrated from INL to ONL. However, maintaining the Müller cells in the ONL for two weeks or longer required repeated injections of bFGF and insulin. Interestingly, all Müller cells in the ONL expressed chx10, a stem cell marker. We did not find any immunolabeling for rhodopsin, m-opsin or s-opsin in the Müller glia in the ONL.
Collapse
Affiliation(s)
- Manvi Goel
- National Brain Research Centre, Manesar, Gurgaon, Haryana 122051, India.
| | | |
Collapse
|
11
|
The Future of Regenerative Medicine: Cell Therapy Using Pluripotent Stem Cells and Acellular Therapies Based on Extracellular Vesicles. Cells 2021; 10:cells10020240. [PMID: 33513719 PMCID: PMC7912181 DOI: 10.3390/cells10020240] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 01/13/2021] [Accepted: 01/23/2021] [Indexed: 12/11/2022] Open
Abstract
The rapid progress in the field of stem cell research has laid strong foundations for their use in regenerative medicine applications of injured or diseased tissues. Growing evidences indicate that some observed therapeutic outcomes of stem cell-based therapy are due to paracrine effects rather than long-term engraftment and survival of transplanted cells. Given their ability to cross biological barriers and mediate intercellular information transfer of bioactive molecules, extracellular vesicles are being explored as potential cell-free therapeutic agents. In this review, we first discuss the state of the art of regenerative medicine and its current limitations and challenges, with particular attention on pluripotent stem cell-derived products to repair organs like the eye, heart, skeletal muscle and skin. We then focus on emerging beneficial roles of extracellular vesicles to alleviate these pathological conditions and address hurdles and operational issues of this acellular strategy. Finally, we discuss future directions and examine how careful integration of different approaches presented in this review could help to potentiate therapeutic results in preclinical models and their good manufacturing practice (GMP) implementation for future clinical trials.
Collapse
|
12
|
Single-cell RNA sequencing in vision research: Insights into human retinal health and disease. Prog Retin Eye Res 2020; 83:100934. [PMID: 33383180 DOI: 10.1016/j.preteyeres.2020.100934] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Revised: 11/27/2020] [Accepted: 12/01/2020] [Indexed: 01/03/2023]
Abstract
Gene expression provides valuable insight into cell function. As such, vision researchers have frequently employed gene expression studies to better understand retinal physiology and disease. With the advent of single-cell RNA sequencing, expression experiments provide an unparalleled resolution of information. Instead of studying aggregated gene expression across all cells in a heterogenous tissue, single-cell technology maps RNA to an individual cell, which facilitates grouping of retinal and choroidal cell types for further study. Single-cell RNA sequencing has been quickly adopted by both basic and translational vision researchers, and single-cell level gene expression has been studied in the visual systems of animal models, retinal organoids, and primary human retina, RPE, and choroid. These experiments have generated detailed atlases of gene expression and identified new retinal cell types. Likewise, single-cell RNA sequencing investigations have characterized how gene expression changes in the setting of many retinal diseases, including how choroidal endothelial cells are altered in age-related macular degeneration. In addition, this technology has allowed vision researchers to discover drivers of retinal development and model rare retinal diseases with induced pluripotent stem cells. In this review, we will overview the growing number of single-cell RNA sequencing studies in the field of vision research. We will summarize experimental considerations for designing single-cell RNA sequencing experiments and highlight important advancements in retinal, RPE, choroidal, and retinal organoid biology driven by this technology. Finally, we generalize these findings to genes involved in retinal degeneration and outline the future of single-cell expression experiments in studying retinal disease.
Collapse
|
13
|
Zhang CJ, Ma Y, Jin ZB. The road to restore vision with photoreceptor regeneration. Exp Eye Res 2020; 202:108283. [PMID: 33010290 DOI: 10.1016/j.exer.2020.108283] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 09/13/2020] [Accepted: 09/24/2020] [Indexed: 12/12/2022]
Abstract
Neuroretinal diseases are the predominant cause of irreversible blindness worldwide, mainly due to photoreceptor loss. Currently, there are no radical treatments to fully reverse the degeneration or even stop the disease progression. Thus, it is urgent to develop new biological therapeutics for these diseases on the clinical side. Stem cell-based treatments have become a promising therapeutic for neuroretinal diseases through the replacement of damaged cells with photoreceptors and some allied cells. To date, considerable efforts have been made to regenerate the diseased retina based on stem cell technology. In this review, we overview the current status of stem cell-based treatments for photoreceptor regeneration, including the major cell sources derived from different stem cells in pre-clinical or clinical trial stages. Additionally, we discuss herein the major challenges ahead for and potential new strategy toward photoreceptor regeneration.
Collapse
Affiliation(s)
- Chang-Jun Zhang
- Laboratory for Stem Cell & Retinal Regeneration, The Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
| | - Ya Ma
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Science Key Laboratory, Beijing, 100730, China
| | - Zi-Bing Jin
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Science Key Laboratory, Beijing, 100730, China.
| |
Collapse
|
14
|
Lin B, McLelland BT, Aramant RB, Thomas BB, Nistor G, Keirstead HS, Seiler MJ. Retina Organoid Transplants Develop Photoreceptors and Improve Visual Function in RCS Rats With RPE Dysfunction. Invest Ophthalmol Vis Sci 2020; 61:34. [PMID: 32945842 PMCID: PMC7509771 DOI: 10.1167/iovs.61.11.34] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Accepted: 08/17/2020] [Indexed: 01/01/2023] Open
Abstract
Purpose To study if human embryonic stem cell-derived photoreceptors could survive and function without the support of retinal pigment epithelium (RPE) after transplantation into Royal College of Surgeons rats, a rat model of retinal degeneration caused by RPE dysfunction. Methods CSC14 human embryonic stem cells were differentiated into primordial eye structures called retinal organoids. Retinal organoids were analyzed by quantitative PCR and immunofluorescence and compared with human fetal retina. Retinal organoid sheets (30-70 day of differentiation) were transplanted into immunodeficient RCS rats, aged 44 to 56 days. The development of transplant organoids in vivo in relation to the host was examined by optical coherence tomography. Visual function was assessed by optokinetic testing, electroretinogram, and superior colliculus electrophysiologic recording. Cryostat sections were analyzed for various retinal, synaptic, and donor markers. Results Retinal organoids showed similar gene expression to human fetal retina transplanted rats demonstrated significant improvement in visual function compared with RCS nonsurgery and sham surgery controls by ERGs at 2 months after surgery (but not later), optokinetic testing (up to 6 months after surgery) and electrophysiologic superior colliculus recordings (6-8 months after surgery). The transplanted organoids survived more than 7 months; developed photoreceptors with inner and outer segments, and other retinal cells; and were well-integrated within the host. Conclusions This study, to our knowledge, is the first to show that transplanted photoreceptors survive and function even with host's dysfunctional RPE. Our findings suggest that transplantation of organoid sheets from stem cells may be a promising approach/therapeutic for blinding diseases.
Collapse
Affiliation(s)
- Bin Lin
- Physical Medicine & Rehabilitation, Sue & Bill Gross Stem Cell Research Center, University of California at Irvine, School of Medicine, Irvine, California, United States
| | - Bryce T. McLelland
- Physical Medicine & Rehabilitation, Sue & Bill Gross Stem Cell Research Center, University of California at Irvine, School of Medicine, Irvine, California, United States
| | - Robert B. Aramant
- Physical Medicine & Rehabilitation, Sue & Bill Gross Stem Cell Research Center, University of California at Irvine, School of Medicine, Irvine, California, United States
| | - Biju B. Thomas
- USC Roski Eye Institute, Department of Ophthalmology, University of Southern California, Los Angeles, California, United States
| | - Gabriel Nistor
- AIVITA Biomedical Inc., Irvine, California, United States
| | | | - Magdalene J. Seiler
- Physical Medicine & Rehabilitation, Sue & Bill Gross Stem Cell Research Center, University of California at Irvine, School of Medicine, Irvine, California, United States
- Ophthalmology, University of California at Irvine, School of Medicine, Irvine, California, United States
- Anatomy & Neurobiology, University of California at Irvine School of Medicine, Irvine, California, United States
| |
Collapse
|
15
|
Bian B, Zhao C, He X, Gong Y, Ren C, Ge L, Zeng Y, Li Q, Chen M, Weng C, He J, Fang Y, Xu H, Yin ZQ. Exosomes derived from neural progenitor cells preserve photoreceptors during retinal degeneration by inactivating microglia. J Extracell Vesicles 2020; 9:1748931. [PMID: 32373289 PMCID: PMC7191912 DOI: 10.1080/20013078.2020.1748931] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 02/12/2020] [Accepted: 03/01/2020] [Indexed: 02/06/2023] Open
Abstract
Retinal degeneration (RD) is one of the most common causes of visual impairment and blindness and is characterized by progressive degeneration of photoreceptors. Transplantation of neural stem/progenitor cells (NPCs) is a promising treatment for RD, although the mechanisms underlying the efficacy remain unclear. Accumulated evidence supports the notion that paracrine effects of transplanted stem cells is likely the major approach to rescuing early degeneration, rather than cell replacement. NPC-derived exosomes (NPC-exos), a type of extracellular vesicles (EVs) released from NPCs, are thought to carry functional molecules to recipient cells and play therapeutic roles. In present study, we found that grafted human NPCs (hNPCs) secreted EVs and exosomes in the subretinal space (SRS) of RCS rats, an RD model. And direct administration of mouse neural progenitor cell-derived exosomes (mNPC-exos) delayed photoreceptor degeneration, preserved visual function, prevented thinning of the outer nuclear layer (ONL), and decreased apoptosis of photoreceptors in RCS rats. Mechanistically, mNPC-exos were specifically internalized by retinal microglia and suppressed their activation in vitro and in vivo. RNA sequencing and miRNA profiling revealed a set of 17 miRNAs contained in mNPC-exos that markedly inhibited inflammatory signal pathways by targeting TNF-α, IL-1β, and COX-2 in activated microglia. The exosomes derived from hNPC (hNPC-exos) contained similar miRNAs to mNPC-exos that inhibited microglial activation. We demonstrated that NPC-exos markedly suppressed microglial activation to protect photoreceptors from apoptosis, suggesting that NPC-exos and their contents may be the mechanism of stem cell therapy for treating RD.
Collapse
Affiliation(s)
- Baishijiao Bian
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, P.R. China.,Key Lab of Visual Damage and Regeneration & Restoration of Chongqing, Chongqing, P.R. China
| | - Congjian Zhao
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, P.R. China.,Key Lab of Visual Damage and Regeneration & Restoration of Chongqing, Chongqing, P.R. China
| | - Xiangyu He
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, P.R. China.,Key Lab of Visual Damage and Regeneration & Restoration of Chongqing, Chongqing, P.R. China
| | - Yu Gong
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, P.R. China.,Key Lab of Visual Damage and Regeneration & Restoration of Chongqing, Chongqing, P.R. China
| | - Chunge Ren
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, P.R. China.,Key Lab of Visual Damage and Regeneration & Restoration of Chongqing, Chongqing, P.R. China
| | - Lingling Ge
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, P.R. China.,Key Lab of Visual Damage and Regeneration & Restoration of Chongqing, Chongqing, P.R. China
| | - Yuxiao Zeng
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, P.R. China.,Key Lab of Visual Damage and Regeneration & Restoration of Chongqing, Chongqing, P.R. China
| | - Qiyou Li
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, P.R. China.,Key Lab of Visual Damage and Regeneration & Restoration of Chongqing, Chongqing, P.R. China
| | - Min Chen
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, P.R. China.,Key Lab of Visual Damage and Regeneration & Restoration of Chongqing, Chongqing, P.R. China
| | - Chuanhuang Weng
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, P.R. China.,Key Lab of Visual Damage and Regeneration & Restoration of Chongqing, Chongqing, P.R. China
| | - Juncai He
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, P.R. China.,Key Lab of Visual Damage and Regeneration & Restoration of Chongqing, Chongqing, P.R. China
| | - Yajie Fang
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, P.R. China.,Key Lab of Visual Damage and Regeneration & Restoration of Chongqing, Chongqing, P.R. China
| | - Haiwei Xu
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, P.R. China.,Key Lab of Visual Damage and Regeneration & Restoration of Chongqing, Chongqing, P.R. China
| | - Zheng Qin Yin
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, P.R. China.,Key Lab of Visual Damage and Regeneration & Restoration of Chongqing, Chongqing, P.R. China
| |
Collapse
|
16
|
Koster C, Wever KE, Wagstaff EL, Hirk KTVD, Hooijmans CR, Bergen AA. A Systematic Review on Transplantation Studies of the Retinal Pigment Epithelium in Animal Models. Int J Mol Sci 2020; 21:E2719. [PMID: 32295315 PMCID: PMC7216090 DOI: 10.3390/ijms21082719] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 04/02/2020] [Accepted: 04/10/2020] [Indexed: 01/18/2023] Open
Abstract
The retinal pigment epithelium (RPE) and the adjacent light-sensitive photoreceptors form a single functional unit lining the back of the eye. Both cell layers are essential for normal vision. RPE degeneration is usually followed by photoreceptor degeneration and vice versa. There are currently almost no effective therapies available for RPE disorders such as Stargardt disease, specific types of retinitis pigmentosa, and age-related macular degeneration. RPE replacement for these disorders, especially in later stages of the disease, may be one of the most promising future therapies. There is, however, no consensus regarding the optimal RPE source, delivery strategy, or the optimal experimental host in which to test RPE replacement therapy. Multiple RPE sources, delivery methods, and recipient animal models have been investigated, with variable results. So far, a systematic evaluation of the (variables influencing) efficacy of experimental RPE replacement parameters is lacking. Here we investigate the effect of RPE transplantation on vision and vision-based behavior in animal models of retinal degenerated diseases. In addition, we aim to explore the effect of RPE source used for transplantation, the method of intervention, and the animal model which is used. METHODS In this study, we systematically identified all publications concerning transplantation of RPE in experimental animal models targeting the improvement of vision (e.g., outcome measurements related to the morphology or function of the eye). A variety of characteristics, such as species, gender, and age of the animals but also cell type, number of cells, and other intervention characteristics were extracted from all studies. A risk of bias analysis was performed as well. Subsequently, all references describing one of the following outcomes were analyzed in depth in this systematic review: a-, b-, and c-wave amplitudes, vision-based, thickness analyses based on optical coherence tomography (OCT) data, and transplant survival based on scanning laser ophthalmoscopy (SLO) data. Meta-analyses were performed on the a- and b-wave amplitudes from electroretinography (ERG) data as well as data from vision-based behavioral assays. RESULTS original research articles met the inclusion criteria after two screening rounds. Overall, most studies were categorized as unclear regarding the risk of bias, because many experimental details were poorly reported. Twenty-three studies reporting one or more of the outcome measures of interest were eligible for either descriptive (thickness analyses based on OCT data; n = 2) or meta-analyses. RPE transplantation significantly increased ERG a-wave (Hedges' g 1.181 (0.471-1.892), n = 6) and b-wave (Hedges' g 1.734 (1.295-2.172), n = 42) amplitudes and improved vision-based behavior (Hedges' g 1.018 (0.826-1.209), n = 96). Subgroup analyses revealed a significantly increased effect of the use of young and adolescent animals compared to adult animals. Moreover, transplanting more cells (in the range of 105 versus in the range of 104) resulted in a significantly increased effect on vision-based behavior as well. The origin of cells mattered as well. A significantly increased effect was found on vision-based behavior when using ARPE-19 and OpRegen® RPE. CONCLUSIONS This systematic review shows that RPE transplantation in animal models for retinal degeneration significantly increases a- and b- wave amplitudes and improves vision-related behavior. These effects appear to be more pronounced in young animals, when the number of transplanted cells is larger and when ARPE-19 and OpRegen® RPE cells are used. We further emphasize that there is an urgent need for improving the reporting and methodological quality of animal experiments, to make such studies more comparable.
Collapse
Affiliation(s)
- Céline Koster
- Department of Clinical Genetics, Amsterdam University Medical Centers (AUMC), Location Academic Medical Center (AMC), University of Amsterdam (UvA), 1105 AZ Amsterdam, The Netherlands
| | - Kimberley E Wever
- Systematic Review Center for Laboratory Animal Experimentation (SYRCLE), Department for Health Evidence, Radboud Institute for Health Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Ellie L Wagstaff
- Department of Clinical Genetics, Amsterdam University Medical Centers (AUMC), Location Academic Medical Center (AMC), University of Amsterdam (UvA), 1105 AZ Amsterdam, The Netherlands
| | - Koen T van den Hirk
- Department of Clinical Genetics, Amsterdam University Medical Centers (AUMC), Location Academic Medical Center (AMC), University of Amsterdam (UvA), 1105 AZ Amsterdam, The Netherlands
| | - Carlijn R Hooijmans
- Systematic Review Center for Laboratory Animal Experimentation (SYRCLE), Department for Health Evidence, Radboud Institute for Health Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
- Department of Anesthesiology, Pain and Palliative Medicine, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Arthur A Bergen
- Department of Clinical Genetics, Amsterdam University Medical Centers (AUMC), Location Academic Medical Center (AMC), University of Amsterdam (UvA), 1105 AZ Amsterdam, The Netherlands
- Department of Ophthalmology, AUMC, AMC, UvA, 1105 AZ Amsterdam, The Netherlands
- Department of Ophthalmogenetics, Netherlands Institute for Neuroscience (NIN-KNAW), 1105 BA Amsterdam, The Netherlands
| |
Collapse
|
17
|
Ben M’Barek K, Habeler W, Regent F, Monville C. Developing Cell-Based Therapies for RPE-Associated Degenerative Eye Diseases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1186:55-97. [DOI: 10.1007/978-3-030-28471-8_3] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
|
18
|
Ma DJ, Lim MS, Park UC, Park JB, Ji SY, Yu HG. Magnetic Iron Oxide Nanoparticle Labeling of Photoreceptor Precursors for Magnetic Resonance Imaging. Tissue Eng Part C Methods 2019; 25:532-542. [PMID: 31418341 DOI: 10.1089/ten.tec.2019.0136] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
IMPACT STATEMENT This study describes the methods and results of superparamagnetic iron oxide nanoparticle (SPION) labeling and magnetic resonance imaging (MRI) tracking of human embryonic stem cell-derived photoreceptor precursors transplanted into the subretinal space of Royal College of Surgeons rats. SPION labeling and MRI tracking provide information about the biodistribution of transplanted photoreceptor precursors, which is necessary for improving the functional benefits of cell therapy for degenerative retinal diseases.
Collapse
Affiliation(s)
- Dae Joong Ma
- Department of Ophthalmology, College of Medicine, Seoul National University, Seoul, Republic of Korea.,Retinal Degeneration Research Lab, Seoul National University Hospital Biomedical Research Institute, Seoul, Republic of Korea
| | - Mi-Sun Lim
- R&D Center, Jeil Pharmaceutical Co., Ltd., Yongin-si, Republic of Korea.,Institute of Reproductive Medicine and Population, Medical Research Center, Seoul National University, Seoul, Republic of Korea
| | - Un Chul Park
- Department of Ophthalmology, College of Medicine, Seoul National University, Seoul, Republic of Korea.,Retinal Degeneration Research Lab, Seoul National University Hospital Biomedical Research Institute, Seoul, Republic of Korea
| | - Jung-Bum Park
- Retinal Degeneration Research Lab, Seoul National University Hospital Biomedical Research Institute, Seoul, Republic of Korea
| | - So Yeon Ji
- R&D Center, Jeil Pharmaceutical Co., Ltd., Yongin-si, Republic of Korea.,Institute of Reproductive Medicine and Population, Medical Research Center, Seoul National University, Seoul, Republic of Korea
| | - Hyeong Gon Yu
- Department of Ophthalmology, College of Medicine, Seoul National University, Seoul, Republic of Korea.,Retinal Degeneration Research Lab, Seoul National University Hospital Biomedical Research Institute, Seoul, Republic of Korea.,Institute of Reproductive Medicine and Population, Medical Research Center, Seoul National University, Seoul, Republic of Korea
| |
Collapse
|
19
|
Alsaeedi HA, Koh AEH, Lam C, Rashid MBA, Harun MHN, Saleh MFBM, Teh SW, Luu CD, Ng MH, Isa HM, Leow SN, Then KY, Bastion MLC, Mok PL, Muthuvenkatachalam BS, Samrot AV, Swamy KB, Nandakumar J, Kumar SS. Dental pulp stem cells therapy overcome photoreceptor cell death and protects the retina in a rat model of sodium iodate-induced retinal degeneration. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2019; 198:111561. [PMID: 31352000 DOI: 10.1016/j.jphotobiol.2019.111561] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 06/10/2019] [Accepted: 07/15/2019] [Indexed: 12/11/2022]
Abstract
Blindness and vision loss contribute to irreversible retinal degeneration, and cellular therapy for retinal cell replacement has the potential to treat individuals who have lost light sensitive photoreceptors in the retina. Retinal cells are well characterized in function, and are a subject of interest in cellular replacement therapy of photoreceptors and the retinal pigment epithelium. However, retinal cell transplantation is limited by various factors, including the choice of potential stem cell source that can show variability in plasticity as well as host tissue integration. Dental pulp is one such source that contains an abundance of stem cells. In this study we used dental pulp-derived mesenchymal stem cells (DPSCs) to mitigate sodium iodate (NaIO3) insult in a rat model of retinal degeneration. Sprague-Dawley rats were first given an intravitreal injection of 3 × 105 DPSCs as well as a single systemic administration of NaIO3 (40 mg/kg). Electroretinography (ERG) was performed for the next two months and was followed-up by histological analysis. The ERG recordings showed protection of DPSC-treated retinas within 4 weeks, which was statistically significant (* P ≤ .05) compared to the control. Retinal thickness of the control was also found to be thinner (*** P ≤ .001). The DPSCs were found integrated in the photoreceptor layer through immunohistochemical staining. Our findings showed that DPSCs have the potential to moderate retinal degeneration. In conclusion, DPSCs are a potential source of stem cells in the field of eye stem cell therapy due to its protective effects against retinal degeneration.
Collapse
Affiliation(s)
- Hiba Amer Alsaeedi
- Department of Medical Microbiology and Parasitology, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
| | - Avin Ee-Hwan Koh
- Department of Biomedical Science, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
| | - Chenshen Lam
- Department of Ophthalmology, Faculty of Medicine, UKM Medical Centre, 56000 Cheras, Kuala Lumpur, Malaysia
| | - Munirah Binti Abd Rashid
- Department of Ophthalmology, Faculty of Medicine, UKM Medical Centre, 56000 Cheras, Kuala Lumpur, Malaysia
| | - Mohd Hairul Nizam Harun
- Department of Ophthalmology, Faculty of Medicine, UKM Medical Centre, 56000 Cheras, Kuala Lumpur, Malaysia.
| | | | - Seoh Wei Teh
- Department of Biomedical Science, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
| | - Chi D Luu
- Centre for Eye Research Australia, Royal Victorian Eye & Ear Hospital, Melbourne 3002, Australia; Department of Surgery (Ophthalmology), the University of Melbourne, Melbourne 3010, Australia.
| | - Min Hwei Ng
- Tissue Engineering Centre, Universiti Kebangsaan Malaysia Medical Center, 56000 Cheras, Kuala Lumpur, Malaysia
| | - Hazlita Mohd Isa
- Department of Ophthalmology, Faculty of Medicine, UKM Medical Centre, 56000 Cheras, Kuala Lumpur, Malaysia
| | - Sue Ngein Leow
- Department of Ophthalmology, Hospital Sultanah Aminah, 80100 Johor Bahru, Johor, Malaysia
| | - Kong Yong Then
- Department of Ophthalmology, Faculty of Medicine, UKM Medical Centre, 56000 Cheras, Kuala Lumpur, Malaysia
| | - Mae-Lynn Catherine Bastion
- Department of Ophthalmology, Faculty of Medicine, UKM Medical Centre, 56000 Cheras, Kuala Lumpur, Malaysia
| | - Pooi Ling Mok
- Department of Biomedical Science, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia; Genetics and Regenerative Medicine Research Center, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia; Department of Clinical Laboratory Sciences, College of Applied Medical Science, Jouf University, Sakaka, P.O Box 2014, Aljouf Province, Saudi Arabia.
| | | | - Antony V Samrot
- Department of Biotechnology, School of Bio and Chemical Engineering, Sathyabama Institute of Science and Technology, Jeppiaar Nagar, Rajiv Gandhi Salai, Sholinganallur, Chennai 600119, Tamil Nadu, India; Department of Biomedical Sciences, Faculty of Medicine and Biomedical Sciences, MAHSA University, Jalan SP2, Bandar Saujana Putra, 42810 Jenjarom, Selangor, Malaysia
| | - K B Swamy
- Faculty of Medicine, Lincoln University College, Wisma Lincoln, No. 12-18, Jalan SS 6/12, 47301 Petaling Jaya, Selangor Darul Ehsan, Malaysia
| | - Jaikumar Nandakumar
- Department of Microbiology, Karpagam University, Eachanari, Coimbatore 641021, Tamil Nadu, India
| | - Suresh Subbiah Kumar
- Department of Medical Microbiology and Parasitology, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia; Genetics and Regenerative Medicine Research Center, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia; Department of Cancer, Institute of Bioscience, Universiti Putra Malaysia, Malaysia.
| |
Collapse
|
20
|
Jones MK, Lu B, Chen DZ, Spivia WR, Mercado AT, Ljubimov AV, Svendsen CN, Van Eyk JE, Wang S. In Vitro and In Vivo Proteomic Comparison of Human Neural Progenitor Cell-Induced Photoreceptor Survival. Proteomics 2019; 19:e1800213. [PMID: 30515959 PMCID: PMC6422354 DOI: 10.1002/pmic.201800213] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 11/01/2018] [Indexed: 12/31/2022]
Abstract
Retinal degenerative diseases lead to blindness with few treatments. Various cell-based therapies are aimed to slow the progression of vision loss by preserving light-sensing photoreceptor cells. A subretinal injection of human neural progenitor cells (hNPCs) into the Royal College of Surgeons (RCS) rat model of retinal degeneration has aided in photoreceptor survival, though the mechanisms are mainly unknown. Identifying the retinal proteomic changes that occur following hNPC treatment leads to better understanding of neuroprotection. To mimic the retinal environment following hNPC injection, a co-culture system of retinas and hNPCs is developed. Less cell death occurs in RCS retinal tissue co-cultured with hNPCs than in retinas cultured alone, suggesting that hNPCs provide retinal protection in vitro. Comparison of ex vivo and in vivo retinas identifies nuclear factor (erythroid-derived 2)-like 2 (NRF2) mediated oxidative response signaling as an hNPC-induced pathway. This is the first study to compare proteomic changes following treatment with hNPCs in both an ex vivo and in vivo environment, further allowing the use of ex vivo modeling for mechanisms of retinal preservation. Elucidation of the protein changes in the retina following hNPC treatment may lead to the discovery of mechanisms of photoreceptor survival and its therapeutic for clinical applications.
Collapse
Affiliation(s)
- Melissa K. Jones
- Department of Biomedical Sciences, Cedars-Sinai Medical Center
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center
| | - Bin Lu
- Department of Biomedical Sciences, Cedars-Sinai Medical Center
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center
| | - Dawn Z. Chen
- Advanced Clinical Biosystems Research Institute, The Smidt Heart Institute, Cedars-Sinai Medical Center
- Department of Medicine, David Geffen School of Medicine, University of California Los Angeles
| | - Weston R. Spivia
- Advanced Clinical Biosystems Research Institute, The Smidt Heart Institute, Cedars-Sinai Medical Center
| | - Augustus T. Mercado
- Department of Biomedical Sciences, Cedars-Sinai Medical Center
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center
| | - Alexander V. Ljubimov
- Department of Biomedical Sciences, Cedars-Sinai Medical Center
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center
- Department of Medicine, David Geffen School of Medicine, University of California Los Angeles
| | - Clive N. Svendsen
- Department of Biomedical Sciences, Cedars-Sinai Medical Center
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center
| | - Jennifer E. Van Eyk
- Advanced Clinical Biosystems Research Institute, The Smidt Heart Institute, Cedars-Sinai Medical Center
- Department of Medicine, David Geffen School of Medicine, University of California Los Angeles
| | - Shaomei Wang
- Department of Biomedical Sciences, Cedars-Sinai Medical Center
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center
- Department of Medicine, David Geffen School of Medicine, University of California Los Angeles
| |
Collapse
|
21
|
Cell Therapy for Retinal Dystrophies: From Cell Suspension Formulation to Complex Retinal Tissue Bioengineering. Stem Cells Int 2019; 2019:4568979. [PMID: 30809263 PMCID: PMC6364130 DOI: 10.1155/2019/4568979] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Accepted: 01/01/2019] [Indexed: 12/25/2022] Open
Abstract
Retinal degeneration is an irreversible phenomenon caused by various disease conditions including age-related macular degeneration (AMD) and retinitis pigmentosa (RP). During the course of these diseases, photoreceptors (PRs) are susceptible to degeneration due to their malfunctions or to a primary dysfunction of the retinal pigment epithelium (RPE). Once lost, these cells could not be endogenously regenerated in humans, and cell therapy to replace the lost cells is one of the promising strategies to recover vision. Depending on the nature of the primary defect and the stage of the disease, RPE cells, PRs, or both might be transplanted to achieve therapeutic effects. We describe in this review the current knowledge and recent progress to develop such approaches. The different cell sources proposed for cell therapy including human pluripotent stem cells are presented with their advantages and limits. Another critical aspect described herein is the pharmaceutical formulation of the end product to be delivered into the eye of patients. Finally, we also outline the future research directions in order to develop a complex multilayered retinal tissue for end-stage patients.
Collapse
|
22
|
Surgical Approaches for Cell Therapeutics Delivery to the Retinal Pigment Epithelium and Retina. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1186:141-170. [PMID: 31654389 DOI: 10.1007/978-3-030-28471-8_6] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Developing successful surgical strategies to deliver cell therapeutics to the back of the eye is an essential pillar to success for stem cell-based applications in blinding retinal diseases. Within this chapter, we have attempted to gather all key considerations during preclinical animal trials.Guidance is provided for choices on animal models, options for immunosuppression, as well as anesthesia. Subsequently we cover surgical strategies for RPE graft delivery, both as suspension as well as in monolayers in small rodents, rabbits, pigs, and nonhuman primate. A detailed account is given in particular on animal variations in vitrectomy and subretinal surgery, which requires a considerable learning curve, when transiting from human to animal. In turn, however, many essential subretinal implantation techniques in large-eyed animals are directly transferrable to human clinical trial protocols.A dedicated subchapter on photoreceptor replacement provides insights on preparation of suspension as well as sheet grafts, to subsequently outline the basics of subretinal delivery via both the transscleral and transvitreal route. In closing, a future outlook on vision restoration through retinal cell-based therapeutics is presented.
Collapse
|
23
|
Thomas BB, Zhu D, Lin TC, Kim YC, Seiler MJ, Martinez-Camarillo JC, Lin B, Shad Y, Hinton DR, Humayun MS. A new immunodeficient retinal dystrophic rat model for transplantation studies using human-derived cells. Graefes Arch Clin Exp Ophthalmol 2018; 256:2113-2125. [PMID: 30215097 DOI: 10.1007/s00417-018-4134-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 08/28/2018] [Accepted: 09/03/2018] [Indexed: 12/11/2022] Open
Abstract
PURPOSE To create new immunodeficient Royal College of Surgeons (RCS) rats by introducing the defective MerTK gene into athymic nude rats. METHODS Female homozygous RCS (RCS-p+/RCS-p+) and male nude rats (Hsd:RH-Foxn1mu, mutation in the foxn1 gene; no T cells) were crossed to produce heterozygous F1 progeny. Double homozygous F2 progeny obtained by crossing the F1 heterozygotes was identified phenotypically (hair loss) and genotypically (RCS-p+ gene determined by PCR). Retinal degenerative status was confirmed by optical coherence tomography (OCT) imaging, electroretinography (ERG), optokinetic (OKN) testing, superior colliculus (SC) electrophysiology, and by histology. The effect of xenografts was assessed by transplantation of human embryonic stem cell-derived retinal pigment epithelium (hESC-RPE) and human-induced pluripotent stem cell-derived RPE (iPS-RPE) into the eye. Morphological analysis was conducted based on hematoxylin and eosin (H&E) and immunostaining. Age-matched pigmented athymic nude rats were used as control. RESULTS Approximately 6% of the F2 pups (11/172) were homozygous for RCS-p+ gene and Foxn1mu gene. Homozygous males crossed with heterozygous females resulted in 50% homozygous progeny for experimentation. OCT imaging demonstrated significant loss of retinal thickness in homozygous rats. H&E staining showed photoreceptor thickness reduced to 1-3 layers at 12 weeks of age. Progressive loss of visual function was evidenced by OKN testing, ERG, and SC electrophysiology. Transplantation experiments demonstrated survival of human-derived cells and absence of apparent immune rejection. CONCLUSIONS This new rat animal model developed by crossing RCS rats and athymic nude rats is suitable for conducting retinal transplantation experiments involving xenografts.
Collapse
Affiliation(s)
- Biju B Thomas
- Department of Ophthalmology, USC Roski Eye Institute, University of Southern California, Los Angeles, CA, 90033, USA.
- USC Institute for Biomedical Therapeutics, University of Southern California, Los Angeles, CA, USA.
| | - Danhong Zhu
- Department of Ophthalmology, USC Roski Eye Institute, University of Southern California, Los Angeles, CA, 90033, USA
- Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Tai-Chi Lin
- Department of Ophthalmology, USC Roski Eye Institute, University of Southern California, Los Angeles, CA, 90033, USA
- USC Institute for Biomedical Therapeutics, University of Southern California, Los Angeles, CA, USA
- Department of Ophthalmology, Taipei Veterans General Hospital, Taipei, Taiwan, Republic of China
- Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan, Republic of China
| | - Young Chang Kim
- Department of Ophthalmology, USC Roski Eye Institute, University of Southern California, Los Angeles, CA, 90033, USA
- Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Magdalene J Seiler
- Department of Physical Medicine & Rehabilitation, University of California-Irvine, Irvine, CA, USA
- Stem Cell Research Center, University of California-Irvine, Irvine, CA, USA
| | - Juan Carlos Martinez-Camarillo
- Department of Ophthalmology, USC Roski Eye Institute, University of Southern California, Los Angeles, CA, 90033, USA
- USC Institute for Biomedical Therapeutics, University of Southern California, Los Angeles, CA, USA
| | - Bin Lin
- Department of Physical Medicine & Rehabilitation, University of California-Irvine, Irvine, CA, USA
- Stem Cell Research Center, University of California-Irvine, Irvine, CA, USA
| | - Yousuf Shad
- Department of Chemistry and Chemical Biology, McMaster University, Hamilton, ON, Canada
| | - David R Hinton
- Department of Ophthalmology, USC Roski Eye Institute, University of Southern California, Los Angeles, CA, 90033, USA
- Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Mark S Humayun
- Department of Ophthalmology, USC Roski Eye Institute, University of Southern California, Los Angeles, CA, 90033, USA
- USC Institute for Biomedical Therapeutics, University of Southern California, Los Angeles, CA, USA
| |
Collapse
|
24
|
McGill TJ, Stoddard J, Renner LM, Messaoudi I, Bharti K, Mitalipov S, Lauer A, Wilson DJ, Neuringer M. Allogeneic iPSC-Derived RPE Cell Graft Failure Following Transplantation Into the Subretinal Space in Nonhuman Primates. Invest Ophthalmol Vis Sci 2018; 59:1374-1383. [PMID: 29625461 PMCID: PMC5846443 DOI: 10.1167/iovs.17-22467] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Purpose To characterize the intraocular immune response following transplantation of iPS-derived allogeneic RPE cells into the subretinal space of non–immune-suppressed rhesus macaques. Methods GFP-labeled allogeneic iPS-derived RPE cells were transplanted into the subretinal space of one eye (n = 6), and into the contralateral eye 1 day to 4 weeks later, using a two-stage transretinal and transscleral approach. Retinas were examined pre- and post-surgery by color fundus photography, fundus autofluorescence, and optical coherence tomography (OCT) imaging. Animals were euthanized between 2 hours and 7 weeks following transplantation. T-cell (CD3), B-cell (CD20), and microglial (Iba1) responses were assessed immunohistochemically. Results Cells were delivered into the subretinal space in all eyes without leakage into the vitreous. Transplanted RPE cells were clearly visible at 4 days after surgery but were no longer detectable by 3 weeks. In localized areas within the bleb containing transplanted cells, T- and B-cell infiltrates and microglia were observed in the subretinal space and underlying choroid. A T-cell response predominated at 4 days, but converted to a B-cell response at 3 weeks. By 7 weeks, few infiltrates or microglia remained. Host RPE and choroid were disrupted in the immediate vicinity of the graft, with fibrosis in the subretinal space. Conclusions Engraftment of allogeneic RPE cells failed following transplantation into the subretinal space of rhesus macaques, likely due to rejection by the immune system. These data underscore the need for autologous cell sources and/or confirmation of adequate immune suppression to ensure survival of transplanted RPE cells.
Collapse
Affiliation(s)
- Trevor J McGill
- Department of Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States.,Department of Neuroscience, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, United States
| | - Jonathan Stoddard
- Department of Neuroscience, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, United States
| | - Lauren M Renner
- Department of Neuroscience, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, United States
| | - Ilhem Messaoudi
- Department of Molecular Biology and Biochemistry, University of California Irvine, Irvine, California, United States
| | - Kapil Bharti
- Unit on Ocular and Stem Cell Translational Research, National Eye Institute/National Institutes of Health, Bethesda, Maryland, United States
| | - Shoukhrat Mitalipov
- Department of Reproductive and Developmental Sciences, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, United States
| | - Andreas Lauer
- Department of Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States
| | - David J Wilson
- Department of Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States
| | - Martha Neuringer
- Department of Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States.,Department of Neuroscience, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, United States
| |
Collapse
|
25
|
Cellular regeneration strategies for macular degeneration: past, present and future. Eye (Lond) 2018; 32:946-971. [PMID: 29503449 PMCID: PMC5944658 DOI: 10.1038/s41433-018-0061-z] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 01/05/2018] [Accepted: 01/15/2018] [Indexed: 01/12/2023] Open
Abstract
Despite considerable effort and significant therapeutic advances, age-related macular degeneration (AMD) remains the commonest cause of blindness in the developed world. Progressive late-stage AMD with outer retinal degeneration currently has no proven treatment. There has been significant interest in the possibility that cellular treatments may slow or reverse visual loss in AMD. A number of modes of action have been suggested, including cell replacement and rescue, as well as immune modulation to delay the neurodegenerative process. Their appeal in this enigmatic disease relate to their generic, non-pathway-specific effects. The outer retina in particular has been at the forefront of developments in cellular regenerative therapies being surgically accessible, easily observable, as well as having a relatively simple architecture. Both the retinal pigment epithelium (RPE) and photoreceptors have been considered for replacement therapies as both sheets and cell suspensions. Studies using autologous RPE, and to a lesser extent, foetal retina, have shown proof of principle. A wide variety of cell sources have been proposed with pluripotent stem cell-derived cells currently holding the centre stage. Recent early-phase trials using these cells for RPE replacement have met safety endpoints and hinted at possible efficacy. Animal studies have confirmed the promise that photoreceptor replacement, even in a completely degenerated outer retina may restore some vision. Many challenges, however, remain, not least of which include avoiding immune rejection, ensuring long-term cellular survival and maximising effect. This review provides an overview of progress made, ongoing studies and challenges ahead.
Collapse
|
26
|
Oswald J, Baranov P. Regenerative medicine in the retina: from stem cells to cell replacement therapy. Ther Adv Ophthalmol 2018; 10:2515841418774433. [PMID: 29998222 PMCID: PMC6016968 DOI: 10.1177/2515841418774433] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Accepted: 02/15/2018] [Indexed: 12/20/2022] Open
Abstract
Following the fast pace of the growing field of stem cell research, retinal cell replacement is finally emerging as a feasible mean to be explored for clinical application. Although neuroprotective treatments are able to slow the progression of retinal degeneration caused by diseases such as age-related macular degeneration and glaucoma, they are insufficient to fully halt disease progression and unable to recover previously lost vision. Comprehensive, technological and intellectual advances over the past years, including the in vitro differentiation of retinal cells at manufacturing scale from embryonic stem (ES) cell and induced pluripotent stem (iPS) cell cultures, progress within the area of retinal disease modeling, and the first clinical trials have started to shape the way towards addressing this treatment gap and translating retinal cell replacement to the clinic. Here, summarize the most recent advances within retinal cell replacement from both a scientific and clinical perspective, and discuss the remaining challenges towards the delivery of the first retinal cell products.
Collapse
Affiliation(s)
- Julia Oswald
- Department of Ophthalmology, Harvard Medical School, Schepens Eye Research Institute, Massachusetts Eye and Ear, 20 Staniford Street, Boston, MA 02114, USA
| | - Petr Baranov
- Department of Ophthalmology, Harvard Medical School, Schepens Eye Research Institute, Massachusetts Eye and Ear, Boston, MA, USA
| |
Collapse
|
27
|
Heo JH, Yoon JA, Ahn EK, Kim H, Urm SH, Oak CO, Yu BC, Lee SJ. Intraperitoneal administration of adipose tissue-derived stem cells for the rescue of retinal degeneration in a mouse model via indigenous CNTF up-regulation by IL-6. J Tissue Eng Regen Med 2017; 12:e1370-e1382. [PMID: 28715614 DOI: 10.1002/term.2522] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Revised: 04/05/2017] [Accepted: 06/20/2017] [Indexed: 12/21/2022]
Abstract
As the world's population begins to age, retinal degeneration is an increasing problem, and various treatment modalities are being developed. However, there have been no therapies for degenerative retinal conditions that are not characterized by neovascularization. We investigated whether transplantation of mouse adipose tissue-derived stem cells (mADSC) into the intraperitoneal space has a rescue effect on NaIO3 -induced retinal degeneration in mice. In this study, mADSC transplantation recovered visual function and preserved the retinal outer layer structure compared to the control group without any integration of mADSC into the retina. Moreover, endogenous ciliary neurotrophic factor (CNTF) was elevated in the retinas of mADSC-treated mice. We found that lipopolysaccharide (LPS) or LPS-stimulated monocyte supernatant induced the secretion of granulocyte colony stimulating factor (GCSF), CD54, CXCL10, interleukin-6 (IL-6), and CCL5 from the mADSC by cytokine array. Network inference was conducted to investigate signaling networks related to CNTF regulation. Based on bioinformatics data, the expression of IL-6 was related to the expression of CNTF. Additionally, intravitreal injection of IL-6 in rats produced up-regulation of endogenous CNTF in the retina. mADSC had a rescue effect on retinal degeneration through the up-regulation of endogenous CNTF by IL-6. Thus, transplantation of mADSC could be a potential treatment option for retinal degeneration.
Collapse
Affiliation(s)
- Jeong Hoon Heo
- Department of Molecular Biology and Immunology, College of Medicine, Kosin University, Pusan, Korea.,Institute for Medicine, College of Medicine, Kosin University, Pusan, Korea
| | - Jung Ae Yoon
- Department of Dental Hygiene, Dong Ju College, Pusan, Korea
| | - Eun Kyung Ahn
- Department of Biological Science, College of Natural Science, Dong-A University, Pusan, Korea
| | - Hyun Kim
- Department of Anatomy, College of Medicine, Kosin University, Pusan, Korea
| | - Sang Hwa Urm
- Department of Preventive Medicine, Inje University College of Medicine, Pusan, Korea
| | - Chul Oh Oak
- Department of Internal Medicine, College of Medicine, Kosin University, Pusan, Korea
| | - Byeng Chul Yu
- Department of Preventive Medicine, College of Medicine, Kosin University, Pusan, Korea
| | - Sang Joon Lee
- Institute for Medicine, College of Medicine, Kosin University, Pusan, Korea.,Department of Ophthalmology, College of Medicine, Kosin University, Pusan, Korea
| |
Collapse
|
28
|
Protective effect of clusterin on rod photoreceptor in rat model of retinitis pigmentosa. PLoS One 2017; 12:e0182389. [PMID: 28767729 PMCID: PMC5540409 DOI: 10.1371/journal.pone.0182389] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Accepted: 07/17/2017] [Indexed: 01/09/2023] Open
Abstract
Retinitis Pigmentosa (RP) begins with the death of rod photoreceptors and is slowly followed by a gradual loss of cones and a rearrangement of the remaining retinal neurons. Clusterin is a chaperone protein that protects cells and is involved in various pathophysiological stresses, including retinal degeneration. Using a well-established transgenic rat model of RP (rhodopsin S334ter), we investigated the effects of clusterin on rod photoreceptor survival. To investigate the role of clusterin in S334ter-line3 retinas, Voronoi analysis and immunohistochemistry were used to evaluate the geometry of rod distribution. Additionally, immunoblot analysis, Bax activation, STAT3 and Akt phosphorylation were used to evaluate the pathway involved in rod cell protection. In this study, clusterin (10μg/ml) intravitreal treatment produced robust preservation of rod photoreceptors in S334ter-line3 retina. The mean number of rods in 1mm2 was significantly greater in clusterin injected RP retinas (postnatal (P) 30, P45, P60, & P75) than in age-matched saline injected RP retinas (P<0.01). Clusterin activated Akt, STAT3 and significantly reduced Bax activity; in addition to inducing phosphorylated STAT3 in Müller cells, which suggests it may indirectly acts on photoreceptors. Thus, clusterin treatment may interferes with mechanisms leading to rod death by suppressing cell death through activation of Akt and STAT3, followed by Bax suppression. Novel insights into the pathway of how clusterin promotes the rod cell survival suggest this treatment may be a potential therapeutic strategy to slow progression of vision loss in human RP.
Collapse
|
29
|
Bracha P, Moore NA, Ciulla TA. Induced pluripotent stem cell-based therapy for age-related macular degeneration. Expert Opin Biol Ther 2017; 17:1113-1126. [PMID: 28664762 DOI: 10.1080/14712598.2017.1346079] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
INTRODUCTION In age-related macular degeneration (AMD), stem cells could possibly replace or regenerate disrupted pathologic retinal pigment epithelium (RPE), and produce supportive growth factors and cytokines such as brain-derived neurotrophic factor. Induced pluripotent stem cells (iPSCs)-derived RPE was first subretinally transplanted in a neovascular AMD patient in 2014. Areas covered: Induced PSCs are derived from the introduction of transcription factors to adult cells under specific cell culture conditions, followed by differentiation into RPE cells. Induced PSC-derived RPE cells exhibit ion transport, membrane potential, polarized VEGF secretion and gene expression that is similar to native RPE. Despite having similar in vitro function, morphology, immunostaining and microscopic analysis, it remains to be seen if iPSC-derived RPE can replicate the myriad of in vivo functions, including immunomodulatory effects, of native RPE cells. Historically, adjuvant RPE transplantation during CNV resections were technically difficult and complicated by immune rejection. Autologous iPSCs are hypothesized to reduce the risk of immune rejection, but their production is time-consuming and expensive. Alternatively, allogenic transplantation using human leukocyte antigen (HLA)-matched iPSCs, similar to HLA-matched organ transplantation, is currently being investigated. Expert opinion: Challenges to successful transplantation with iPSCs include surgical technique, a pathologic subretinal microenvironment, possible immune rejection, and complications of immunosuppression.
Collapse
Affiliation(s)
- Peter Bracha
- a Glick Eye Institute, Department of Ophthalmology , Indiana University School of Medicine , Indianapolis , IN , USA
| | - Nicholas A Moore
- a Glick Eye Institute, Department of Ophthalmology , Indiana University School of Medicine , Indianapolis , IN , USA
| | - Thomas A Ciulla
- a Glick Eye Institute, Department of Ophthalmology , Indiana University School of Medicine , Indianapolis , IN , USA.,b Retina Service , Midwest Eye Institute , Indianapolis , IN , USA
| |
Collapse
|
30
|
Canto-Soler V, Flores-Bellver M, Vergara MN. Stem Cell Sources and Their Potential for the Treatment of Retinal Degenerations. Invest Ophthalmol Vis Sci 2017; 57:ORSFd1-9. [PMID: 27116661 PMCID: PMC6892419 DOI: 10.1167/iovs.16-19127] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Stem cells offer unprecedented opportunities for the development of strategies geared toward the treatment of retinal degenerative diseases. A variety of cellular sources have been investigated for various potential clinical applications, including tissue regeneration, disease modeling, and screening for non–cell-based therapeutic agents. As the field transitions from more than a decade of preclinical research to the first phase I/II clinical trials, we provide a concise overview of the stem cell sources most commonly used, weighing their therapeutic potential on the basis of their technical strengths/limitations, their ethical implications, and the extent of the progress achieved to date. This article serves as a framework for further in-depth analyses presented in the following chapters of this Special Issue.
Collapse
|
31
|
Jones MK, Lu B, Girman S, Wang S. Cell-based therapeutic strategies for replacement and preservation in retinal degenerative diseases. Prog Retin Eye Res 2017; 58:1-27. [PMID: 28111323 PMCID: PMC5441967 DOI: 10.1016/j.preteyeres.2017.01.004] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Revised: 01/08/2017] [Accepted: 01/17/2017] [Indexed: 12/13/2022]
Abstract
Cell-based therapeutics offer diverse options for treating retinal degenerative diseases, such as age-related macular degeneration (AMD) and retinitis pigmentosa (RP). AMD is characterized by both genetic and environmental risks factors, whereas RP is mainly a monogenic disorder. Though treatments exist for some patients with neovascular AMD, a majority of retinal degenerative patients have no effective therapeutics, thus indicating a need for universal therapies to target diverse patient populations. Two main cell-based mechanistic approaches are being tested in clinical trials. Replacement therapies utilize cell-derived retinal pigment epithelial (RPE) cells to supplant lost or defective host RPE cells. These cells are similar in morphology and function to native RPE cells and can potentially supplant the responsibilities of RPE in vivo. Preservation therapies utilize supportive cells to aid in visual function and photoreceptor preservation partially by neurotrophic mechanisms. The goal of preservation strategies is to halt or slow the progression of disease and maintain remaining visual function. A number of clinical trials are testing the safety of replacement and preservation cell therapies in patients; however, measures of efficacy will need to be further evaluated. In addition, a number of prevailing concerns with regards to the immune-related response, longevity, and functionality of the grafted cells will need to be addressed in future trials. This review will summarize the current status of cell-based preclinical and clinical studies with a focus on replacement and preservation strategies and the obstacles that remain regarding these types of treatments.
Collapse
Affiliation(s)
- Melissa K Jones
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA; Department of Biomedical Sciences, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA
| | - Bin Lu
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA; Department of Biomedical Sciences, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA
| | - Sergey Girman
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA; Department of Biomedical Sciences, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA
| | - Shaomei Wang
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA; Department of Biomedical Sciences, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA; David Geffen School of Medicine, University of California Los Angeles, 10833 Le Conte Ave., Los Angeles, CA 90095, USA.
| |
Collapse
|
32
|
Structural divergence of essential triad ribbon synapse proteins among placental mammals - Implications for preclinical trials in photoreceptor transplantation therapy. Exp Eye Res 2017; 159:156-167. [PMID: 28322827 DOI: 10.1016/j.exer.2017.03.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Revised: 01/24/2017] [Accepted: 03/17/2017] [Indexed: 11/22/2022]
Abstract
As photoreceptor transplantation rapidly moves closer to the clinic, verifying graft efficacy in animal models may have unforeseen xenogeneic barriers. Although photoreceptor transplants have most convincingly exhibited functional synaptogenesis in conspecific studies, such evidence (while ruling out false-positives due to: viral graft labeling, fusion/cytosolic transfer, or neuroprotection) has not yet been shown for discordant xenografts. From this, a fundamental question should be raised: is useful xenosynaptogenesis likely between human photoreceptors and mouse retina? The triad ribbon synapse (TRS) that would normally form is unique and contains trans-synaptic proteins essential to its formation and function. Thus, could interspecific structural divergence be present that may inhibit this trans-synaptic bridge in discordant xenografts? In an effort to address this question computationally, we compared eight recently confirmed (including subcellular location) TRS specific (or predominantly expressed at the TRS) proteins among placental mammals (1-to-1 orthologs) using HyPhy selection analysis (a predictive measure of structural divergence) and by using Phyre2 tertiary structural modeling. Here, selection analysis revealed strong positive (diversifying) selection acting on a particularly important TRS protein: pikachurin. This positive selection was localized to its second Laminin-G (LG)-like domain and on its N-terminal domain - a putative region of trans-synaptic interaction. Localization of structural divergence to the N-terminus of each putative post-translational cleavage (PTC) product may suggest neofunctionalization from ancestral uncleaved pikachurin - this would be consistent with a recent counter-paradigm report of pikachurin cleavage predominating at the TRS. From this, we suggest a dual role after cleavage where the N-terminal fragment can still mediate the trans-synaptic bridge, while the C-terminal fragment may act as a diffusible trophic or "homing" factor for bipolar cell dendrite migration. Tertiary structural models mirrored the conformational divergence predicted by selection analysis. With human and mouse pikachurin (as well as other TRS proteins) likely to diverge considerably in structure among placental mammals - alongside known inter-mammalian variation in TRS phenotype and protein repertoire, high levels of diversifying selection acting on genes involving sensation, considerable timespans allowing for genetic drift that can create xenogeneic epistasis, and uncertainty surrounding the extent of xenosynaptogenesis in PPC transplant studies to date - use of distantly related hosts to test human photoreceptor graft therapeutic efficacy should be considered with caution.
Collapse
|
33
|
Goldberg NRS, Marsh SE, Ochaba J, Shelley BC, Davtyan H, Thompson LM, Steffan JS, Svendsen CN, Blurton-Jones M. Human Neural Progenitor Transplantation Rescues Behavior and Reduces α-Synuclein in a Transgenic Model of Dementia with Lewy Bodies. Stem Cells Transl Med 2017; 6:1477-1490. [PMID: 28225193 PMCID: PMC5464354 DOI: 10.1002/sctm.16-0362] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 12/11/2016] [Accepted: 01/06/2017] [Indexed: 12/16/2022] Open
Abstract
Synucleinopathies are a group of neurodegenerative disorders sharing the common feature of misfolding and accumulation of the presynaptic protein α‐synuclein (α‐syn) into insoluble aggregates. Within this diverse group, Dementia with Lewy Bodies (DLB) is characterized by the aberrant accumulation of α‐syn in cortical, hippocampal, and brainstem neurons, resulting in multiple cellular stressors that particularly impair dopamine and glutamate neurotransmission and related motor and cognitive function. Recent studies show that murine neural stem cell (NSC) transplantation can improve cognitive or motor function in transgenic models of Alzheimer's and Huntington's disease, and DLB. However, examination of clinically relevant human NSCs in these models is hindered by the challenges of xenotransplantation and the confounding effects of immunosuppressant drugs on pathology and behavior. To address this challenge, we developed an immune‐deficient transgenic model of DLB that lacks T‐, B‐, and NK‐cells, yet exhibits progressive accumulation of human α‐syn (h‐α‐syn)‐laden inclusions and cognitive and motor impairments. We demonstrate that clinically relevant human neural progenitor cells (line CNS10‐hNPCs) survive, migrate extensively and begin to differentiate preferentially into astrocytes following striatal transplantation into this DLB model. Critically, grafted CNS10‐hNPCs rescue both cognitive and motor deficits after 1 and 3 months and, furthermore, restore striatal dopamine and glutamate systems. These behavioral and neurochemical benefits are likely achieved by reducing α‐syn oligomers. Collectively, these results using a new model of DLB demonstrate that hNPC transplantation can impact a broad array of disease mechanisms and phenotypes and suggest a cellular therapeutic strategy that should be pursued. Stem Cells Translational Medicine2017;6:1477–1490
Collapse
Affiliation(s)
- Natalie R S Goldberg
- Department of Neurobiology and Behavior, Irvine, California, USA.,Sue and Bill Gross Stem Cell Research Center, Irvine, California, USA.,Institute for Memory Impairments and Neurological Disorders, Irvine, California, USA
| | - Samuel E Marsh
- Department of Neurobiology and Behavior, Irvine, California, USA.,Sue and Bill Gross Stem Cell Research Center, Irvine, California, USA.,Institute for Memory Impairments and Neurological Disorders, Irvine, California, USA
| | - Joseph Ochaba
- Department of Neurobiology and Behavior, Irvine, California, USA.,Institute for Memory Impairments and Neurological Disorders, Irvine, California, USA
| | - Brandon C Shelley
- Department of Biomedical Sciences, Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Hayk Davtyan
- Department of Molecular Immunology, Institute for Molecular Medicine, Huntington Beach, California, USA
| | - Leslie M Thompson
- Department of Neurobiology and Behavior, Irvine, California, USA.,Sue and Bill Gross Stem Cell Research Center, Irvine, California, USA.,Institute for Memory Impairments and Neurological Disorders, Irvine, California, USA.,Department of Psychiatry and Human Behavior, University of California, Irvine, California, USA
| | - Joan S Steffan
- Department of Psychiatry and Human Behavior, University of California, Irvine, California, USA
| | - Clive N Svendsen
- Department of Biomedical Sciences, Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Mathew Blurton-Jones
- Department of Neurobiology and Behavior, Irvine, California, USA.,Sue and Bill Gross Stem Cell Research Center, Irvine, California, USA.,Institute for Memory Impairments and Neurological Disorders, Irvine, California, USA
| |
Collapse
|
34
|
Park SS, Moisseiev E, Bauer G, Anderson JD, Grant MB, Zam A, Zawadzki RJ, Werner JS, Nolta JA. Advances in bone marrow stem cell therapy for retinal dysfunction. Prog Retin Eye Res 2017; 56:148-165. [PMID: 27784628 PMCID: PMC5237620 DOI: 10.1016/j.preteyeres.2016.10.002] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 10/11/2016] [Accepted: 10/18/2016] [Indexed: 12/21/2022]
Abstract
The most common cause of untreatable vision loss is dysfunction of the retina. Conditions, such as age-related macular degeneration, diabetic retinopathy and glaucoma remain leading causes of untreatable blindness worldwide. Various stem cell approaches are being explored for treatment of retinal regeneration. The rationale for using bone marrow stem cells to treat retinal dysfunction is based on preclinical evidence showing that bone marrow stem cells can rescue degenerating and ischemic retina. These stem cells have primarily paracrine trophic effects although some cells can directly incorporate into damaged tissue. Since the paracrine trophic effects can have regenerative effects on multiple cells in the retina, the use of this cell therapy is not limited to a particular retinal condition. Autologous bone marrow-derived stem cells are being explored in early clinical trials as therapy for various retinal conditions. These bone marrow stem cells include mesenchymal stem cells, mononuclear cells and CD34+ cells. Autologous therapy requires no systemic immunosuppression or donor matching. Intravitreal delivery of CD34+ cells and mononuclear cells appears to be tolerated and is being explored since some of these cells can home into the damaged retina after intravitreal administration. The safety of intravitreal delivery of mesenchymal stem cells has not been well established. This review provides an update of the current evidence in support of the use of bone marrow stem cells as treatment for retinal dysfunction. The potential limitations and complications of using certain forms of bone marrow stem cells as therapy are discussed. Future directions of research include methods to optimize the therapeutic potential of these stem cells, non-cellular alternatives using extracellular vesicles, and in vivo high-resolution retinal imaging to detect cellular changes in the retina following cell therapy.
Collapse
Affiliation(s)
- Susanna S Park
- Department of Ophthalmology & Vision Science, University of California Davis, Sacramento, CA, 95817, USA.
| | - Elad Moisseiev
- Department of Ophthalmology & Vision Science, University of California Davis, Sacramento, CA, 95817, USA.
| | - Gerhard Bauer
- Stem Cell Program, Institute for Regenerative Cures, University of California Davis, Sacramento, CA, 95817, USA.
| | - Johnathon D Anderson
- Stem Cell Program, Institute for Regenerative Cures, University of California Davis, Sacramento, CA, 95817, USA.
| | - Maria B Grant
- Department of Ophthalmology, Glick Eye Institute, Indiana University, Indianapolis, IN, USA.
| | - Azhar Zam
- UC Davis RISE Eye-Pod Small Animal Imaging Laboratory, Department of Cell Biology and Human Anatomy, University of California Davis, Davis, CA, USA.
| | - Robert J Zawadzki
- Department of Ophthalmology & Vision Science, University of California Davis, Sacramento, CA, 95817, USA; UC Davis RISE Eye-Pod Small Animal Imaging Laboratory, Department of Cell Biology and Human Anatomy, University of California Davis, Davis, CA, USA.
| | - John S Werner
- Department of Ophthalmology & Vision Science, University of California Davis, Sacramento, CA, 95817, USA.
| | - Jan A Nolta
- Stem Cell Program, Institute for Regenerative Cures, University of California Davis, Sacramento, CA, 95817, USA.
| |
Collapse
|
35
|
Bakondi B, Girman S, Lu B, Wang S. Multimodal Delivery of Isogenic Mesenchymal Stem Cells Yields Synergistic Protection from Retinal Degeneration and Vision Loss. Stem Cells Transl Med 2016; 6:444-457. [PMID: 28191768 PMCID: PMC5442813 DOI: 10.5966/sctm.2016-0181] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Accepted: 07/28/2016] [Indexed: 12/30/2022] Open
Abstract
We previously demonstrated that subretinal injection (SRI) of isogenic mesenchymal stem cells (MSCs) reduced the severity of retinal degeneration in Royal College of Surgeons rats in a focal manner. In contrast, intravenous MSC infusion (MSCIV ) produced panoptic retinal rescue. By combining these treatments, we now show that MSCIV supplementation potentiates the MSCSRI -mediated rescue of photoreceptors and visual function. Electrophysiological recording from superior colliculi revealed 3.9-fold lower luminance threshold responses (LTRs) and 22% larger functional rescue area from combined treatment compared with MSCSRI alone. MSCIV supplementation of sham (saline) injection also improved LTRs 3.4-fold and enlarged rescue areas by 27% compared with saline alone. We confirmed the involvement of MSC chemotaxis for vision rescue by modulating C-X-C chemokine receptor 4 activity before MSCIV but without increased retinal homing. Rather, circulating platelets and lymphocytes were reduced 3 and 7 days after MSCIV , respectively. We demonstrated MSCSRI -mediated paracrine support of vision rescue by SRI of concentrated MSC-conditioned medium and assessed function by electroretinography and optokinetic response. MSC-secreted peptides increased retinal pigment epithelium (RPE) metabolic activity and clearance of photoreceptor outer segments ex vivo, which was partially abrogated by antibody blockade of trophic factors in concentrated MSC-conditioned medium, or their cognate receptors on RPE. These data support multimodal mechanisms for MSC-mediated retinal protection that differ by administration route and synergize when combined. Thus, using MSCIV as adjuvant therapy might improve cell therapies for retinal dystrophy and warrants further translational evaluation. Stem Cells Translational Medicine 2017;6:444-457.
Collapse
Affiliation(s)
- Benjamin Bakondi
- Board of Governors Regenerative Medicine Institute, Department of Biomedical Sciences, Cedars‐Sinai Medical Center, Los Angeles, California, USA
| | - Sergey Girman
- Board of Governors Regenerative Medicine Institute, Department of Biomedical Sciences, Cedars‐Sinai Medical Center, Los Angeles, California, USA
| | - Bin Lu
- Board of Governors Regenerative Medicine Institute, Department of Biomedical Sciences, Cedars‐Sinai Medical Center, Los Angeles, California, USA
| | - Shaomei Wang
- Board of Governors Regenerative Medicine Institute, Department of Biomedical Sciences, Cedars‐Sinai Medical Center, Los Angeles, California, USA
| |
Collapse
|
36
|
Wu N, Wang Y, Yang L, Cho KS. Signaling Networks of Retinal Ganglion Cell Formation and the Potential Application of Stem Cell–Based Therapy in Retinal Degenerative Diseases. Hum Gene Ther 2016; 27:609-20. [PMID: 27466076 DOI: 10.1089/hum.2016.083] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Affiliation(s)
- Nan Wu
- 1 Department of Ophthalmology, Southwest Eye Hospital, Southwest Hospital, Third Military Medical University , Chongqing, China
| | - Yi Wang
- 1 Department of Ophthalmology, Southwest Eye Hospital, Southwest Hospital, Third Military Medical University , Chongqing, China
| | - Lanbo Yang
- 2 Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School , Boston, Massachusetts
| | - Kin-Sang Cho
- 2 Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School , Boston, Massachusetts
| |
Collapse
|
37
|
Semo M, Haamedi N, Stevanato L, Carter D, Brooke G, Young M, Coffey P, Sinden J, Patel S, Vugler A. Efficacy and Safety of Human Retinal Progenitor Cells. Transl Vis Sci Technol 2016; 5:6. [PMID: 27486556 PMCID: PMC4959814 DOI: 10.1167/tvst.5.4.6] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Accepted: 05/11/2016] [Indexed: 01/08/2023] Open
Abstract
PURPOSE We assessed the long-term efficacy and safety of human retinal progenitor cells (hRPC) using established rodent models. METHODS Efficacy of hRPC was tested initially in Royal College of Surgeons (RCS) dystrophic rats immunosuppressed with cyclosporine/dexamethasone. Due to adverse effects of dexamethasone, this drug was omitted from a subsequent dose-ranging study, where different hRPC doses were tested for their ability to preserve visual function (measured by optokinetic head tracking) and retinal structure in RCS rats at 3 to 6 months after grafting. Safety of hRPC was assessed by subretinal transplantation into wild type (WT) rats and NIH-III nude mice, with analysis at 3 to 6 and 9 months after grafting, respectively. RESULTS The optimal dose of hRPC for preserving visual function/retinal structure in dystrophic rats was 50,000 to 100,000 cells. Human retinal progenitor cells integrated/survived in dystrophic and WT rat retina up to 6 months after grafting and expressed nestin, vimentin, GFAP, and βIII tubulin. Vision and retinal structure remained normal in WT rats injected with hRPC and there was no evidence of tumors. A comparison between dexamethasone-treated and untreated dystrophic rats at 3 months after grafting revealed an unexpected reduction in the baseline visual acuity of dexamethasone-treated animals. CONCLUSIONS Human retinal progenitor cells appear safe and efficacious in the preclinical models used here. TRANSLATIONAL RELEVANCE Human retinal progenitor cells could be deployed during early stages of retinal degeneration or in regions of intact retina, without adverse effects on visual function. The ability of dexamethasone to reduce baseline visual acuity in RCS dystrophic rats has important implications for the interpretation of preclinical and clinical cell transplant studies.
Collapse
Affiliation(s)
- Ma'ayan Semo
- Department of Ocular Biology and Therapeutics, UCL-Institute of Ophthalmology, London, UK
| | - Nasrin Haamedi
- Department of Ocular Biology and Therapeutics, UCL-Institute of Ophthalmology, London, UK
| | | | - David Carter
- Department of Ocular Biology and Therapeutics, UCL-Institute of Ophthalmology, London, UK
| | | | - Michael Young
- Massachusetts Eye and Ear, Schepens Eye Research Institute, Boston, MA, USA
| | - Peter Coffey
- Department of Ocular Biology and Therapeutics, UCL-Institute of Ophthalmology, London, UK
| | | | | | - Anthony Vugler
- Department of Ocular Biology and Therapeutics, UCL-Institute of Ophthalmology, London, UK
| |
Collapse
|
38
|
Human neural progenitor cells decrease photoreceptor degeneration, normalize opsin distribution and support synapse structure in cultured porcine retina. Brain Res 2016; 1646:522-534. [PMID: 27369448 DOI: 10.1016/j.brainres.2016.06.039] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Revised: 05/27/2016] [Accepted: 06/27/2016] [Indexed: 11/24/2022]
Abstract
Retinal neurodegenerative disorders like retinitis pigmentosa, age-related macular degeneration, diabetic retinopathy and retinal detachment decrease retinal functionality leading to visual impairment. The pathological events are characterized by photoreceptor degeneration, synaptic disassembly, remodeling of postsynaptic neurons and activation of glial cells. Despite intense research, no effective treatment has been found for these disorders. The current study explores the potential of human neural progenitor cell (hNPC) derived factors to slow the degenerative processes in adult porcine retinal explants. Retinas were cultured for 3 days with or without hNPCs as a feeder layer and investigated by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL), immunohistochemical, western blot and quantitative real time-polymerase chain reaction (qRT-PCR) techniques. TUNEL showed that hNPCs had the capacity to limit photoreceptor cell death. Among cone photoreceptors, hNPC coculture resulted in better maintenance of cone outer segments and reduced opsin mislocalization. Additionally, maintained synaptic structural integrity and preservation of second order calbindin positive horizontal cells was also observed. However, Müller cell gliosis only seemed to be alleviated in terms of reduced Müller cell density. Our observations indicate that at 3 days of coculture, hNPC derived factors had the capacity to protect photoreceptors, maintain synaptic integrity and support horizontal cell survival. Human neural progenitor cell applied treatment modalities may be an effective strategy to help maintain retinal functionality in neurodegenerative pathologies. Whether hNPCs can independently hinder Müller cell gliosis by utilizing higher concentrations or by combination with other pharmacological agents still needs to be determined.
Collapse
|
39
|
Gene expression changes in the retina following subretinal injection of human neural progenitor cells into a rodent model for retinal degeneration. Mol Vis 2016; 22:472-90. [PMID: 27217715 PMCID: PMC4872275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 05/13/2016] [Indexed: 12/03/2022] Open
Abstract
PURPOSE Retinal degenerative diseases (RDDs) affect millions of people and are the leading cause of vision loss. Although treatment options for RDDs are limited, stem and progenitor cell-based therapies have great potential to halt or slow the progression of vision loss. Our previous studies have shown that a single subretinal injection of human forebrain derived neural progenitor cells (hNPCs) into the Royal College of Surgeons (RCS) retinal degenerate rat offers long-term preservation of photoreceptors and visual function. Furthermore, neural progenitor cells are currently in clinical trials for treating age-related macular degeneration; however, the molecular mechanisms of stem cell-based therapies are largely unknown. This is the first study to analyze gene expression changes in the retina of RCS rats following subretinal injection of hNPCs using high-throughput sequencing. METHODS RNA-seq data of retinas from RCS rats injected with hNPCs (RCS(hNPCs)) were compared to sham surgery in RCS (RCS(sham)) and wild-type Long Evans (LE(sham)) rats. Differential gene expression patterns were determined with in silico analysis and confirmed with qRT-PCR. Function, biologic, cellular component, and pathway analyses were performed on differentially expressed genes and investigated with immunofluorescent staining experiments. RESULTS Analysis of the gene expression data sets identified 1,215 genes that were differentially expressed between RCS(sham) and LE(sham) samples. Additionally, 283 genes were differentially expressed between the RCS(hNPCs) and RCS(sham) samples. Comparison of these two gene sets identified 68 genes with inverse expression (termed rescue genes), including Pdc, Rp1, and Cdc42ep5. Functional, biologic, and cellular component analyses indicate that the immune response is enhanced in RCS(sham). Pathway analysis of the differential expression gene sets identified three affected pathways in RCS(hNPCs), which all play roles in phagocytosis signaling. Immunofluorescent staining detected the increased presence of macrophages and microglia in RCS(sham) retinas, which decreased in RCS(hNPCs) retinas similar to the patterns detected in LE(sham). CONCLUSIONS The results from this study provide evidence of the gene expression changes that occur following treatment with hNPCs in the degenerating retina. This information can be used in future studies to potentially enhance or predict responses to hNPC and other stem cell therapies for retinal degenerative diseases.
Collapse
|
40
|
Davis RJ, Blenkinsop TA, Campbell M, Borden SM, Charniga CJ, Lederman PL, Frye AM, Aguilar V, Zhao C, Naimark M, Kiehl TR, Temple S, Stern JH. Human RPE Stem Cell-Derived RPE Preserves Photoreceptors in the Royal College of Surgeons Rat: Method for Quantifying the Area of Photoreceptor Sparing. J Ocul Pharmacol Ther 2016; 32:304-9. [PMID: 27182605 DOI: 10.1089/jop.2015.0162] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
PURPOSE Numerous preclinical studies have shown that transplantation of stem cell-derived retinal pigment epithelial cell (RPE) preserves photoreceptor cell anatomy in the dystrophic Royal College of Surgeons (RCS) rat. How rescue is spatially distributed over the eye, relative to the transplantation site, is less clear. To understand spatial variations in transplant efficacy, we have developed a method to measure the spatial distribution of rescued photoreceptor cells. METHODS Human RPE Stem Cell-derived RPE (RPESC-RPE) cells were subretinally injected into RCS rat eyes. After tissue recovery and orientating the globe, a series of retinal sections were cut through the injected area. Sections were stained with DAPI (4',6-diamidino-2-phenylindole) and a number of photoreceptor nuclei were counted across the nasal-temporal and superior-inferior axes. These data were used to construct 2D maps of the area of photoreceptor cell saving. RESULTS Photoreceptor cell preservation was detected in the injected temporal hemisphere and occupied areas greater than 4 mm(2) centered near the injection sites. Rescue was directed toward the central retina and superior and inferior poles, with maximal number of rescued photoreceptor cells proximal to the injection sites. CONCLUSIONS RPESC-RPE transplantation preserves RCS photoreceptor cells. The photoreceptor cell contour maps readily convey the extent of rescue across the eye. The consistent alignment and quantification of results using this method allow the application of other downstream statistical analyses and comparisons to better understand transplantation therapy in the eye.
Collapse
Affiliation(s)
| | | | | | | | | | | | - Amber M Frye
- 1 Neural Stem Cell Institute , Rensselaer, New York
| | | | - Cuiping Zhao
- 1 Neural Stem Cell Institute , Rensselaer, New York
| | | | | | - Sally Temple
- 1 Neural Stem Cell Institute , Rensselaer, New York
| | | |
Collapse
|
41
|
Riera M, Fontrodona L, Albert S, Ramirez DM, Seriola A, Salas A, Muñoz Y, Ramos D, Villegas-Perez MP, Zapata MA, Raya A, Ruberte J, Veiga A, Garcia-Arumi J. Comparative study of human embryonic stem cells (hESC) and human induced pluripotent stem cells (hiPSC) as a treatment for retinal dystrophies. Mol Ther Methods Clin Dev 2016; 3:16010. [PMID: 27006969 PMCID: PMC4793806 DOI: 10.1038/mtm.2016.10] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Accepted: 01/27/2016] [Indexed: 12/30/2022]
Abstract
Retinal dystrophies (RD) are major causes of familial blindness and are characterized by progressive dysfunction of photoreceptor and/or retinal pigment epithelium (RPE) cells. In this study, we aimed to evaluate and compare the therapeutic effects of two pluripotent stem cell (PSC)-based therapies. We differentiated RPE from human embryonic stem cells (hESCs) or human-induced pluripotent stem cells (hiPSCs) and transplanted them into the subretinal space of the Royal College of Surgeons (RCS) rat. Once differentiated, cells from either source of PSC resembled mature RPE in their morphology and gene expression profile. Following transplantation, both hESC- and hiPSC-derived cells maintained the expression of specific RPE markers, lost their proliferative capacity, established tight junctions, and were able to perform phagocytosis of photoreceptor outer segments. Remarkably, grafted areas showed increased numbers of photoreceptor nuclei and outer segment disk membranes. Regardless of the cell source, human transplants protected retina from cell apoptosis, glial stress and accumulation of autofluorescence, and responded better to light stimuli. Altogether, our results show that hESC- and hiPSC-derived cells survived, migrated, integrated, and functioned as RPE in the RCS rat retina, providing preclinical evidence that either PSC source could be of potential benefit for treating RD.
Collapse
Affiliation(s)
- Marina Riera
- Ophthalmology Research, Vall d’Hebron Research Institute (VHIR), Barcelona, Spain
- Institut de Microcirurgia Ocular (IMO), Barcelona, Spain
| | - Laura Fontrodona
- Ophthalmology Research, Vall d’Hebron Research Institute (VHIR), Barcelona, Spain
| | - Silvia Albert
- Center of Regenerative Medicine in Barcelona (CMRB), Barcelona, Spain
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Diana Mora Ramirez
- Ophthalmology Research, Vall d’Hebron Research Institute (VHIR), Barcelona, Spain
- Department of Surgery, Faculty of Medicine, Universitat Autònoma de Barcelona Bellaterra, Spain
| | - Anna Seriola
- Center of Regenerative Medicine in Barcelona (CMRB), Barcelona, Spain
| | - Anna Salas
- Ophthalmology Research, Vall d’Hebron Research Institute (VHIR), Barcelona, Spain
| | - Yolanda Muñoz
- Center of Regenerative Medicine in Barcelona (CMRB), Barcelona, Spain
| | - David Ramos
- Center of Animal Biotechnology and Gene Therapy (CBATEG), Universitat Autònoma de Barcelona, Bellaterra, Spain
- CIISA, Faculdade de Medicina Veterinaria, Universidade de Lisboa, Lisboa, Portugal
| | | | - Miguel Angel Zapata
- Ophthalmology Research, Vall d’Hebron Research Institute (VHIR), Barcelona, Spain
| | - Angel Raya
- Center of Regenerative Medicine in Barcelona (CMRB), Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
- Center for Networked Biomedical Research on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Madrid, Spain
| | - Jesus Ruberte
- Center of Animal Biotechnology and Gene Therapy (CBATEG), Universitat Autònoma de Barcelona, Bellaterra, Spain
- CIISA, Faculdade de Medicina Veterinaria, Universidade de Lisboa, Lisboa, Portugal
- Department of Anatomy and Animal Health, School of Veterinary Medicine, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Anna Veiga
- Center of Regenerative Medicine in Barcelona (CMRB), Barcelona, Spain
| | - Jose Garcia-Arumi
- Ophthalmology Research, Vall d’Hebron Research Institute (VHIR), Barcelona, Spain
- Institut de Microcirurgia Ocular (IMO), Barcelona, Spain
| |
Collapse
|
42
|
Zarbin M. Cell-Based Therapy for Degenerative Retinal Disease. Trends Mol Med 2016; 22:115-134. [PMID: 26791247 DOI: 10.1016/j.molmed.2015.12.007] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2015] [Revised: 12/16/2015] [Accepted: 12/17/2015] [Indexed: 12/21/2022]
Abstract
Stem cell-derived retinal pigment epithelium (RPE) and photoreceptors (PRs) have restored vision in preclinical models of human retinal degenerative disease. This review discusses characteristics of stem cell therapy in the eye and the challenges to clinical implementation that are being confronted today. Based on encouraging results from Phase I/II trials, the first Phase II clinical trials of stem cell-derived RPE transplantation are underway. PR transplant experiments have demonstrated restoration of visual function in preclinical models of retinitis pigmentosa and macular degeneration, but also indicate that no single approach is likely to succeed in overcoming PR loss in all cases. A greater understanding of the mechanisms controlling synapse formation as well as the immunoreactivity of transplanted retinal cells is urgently needed.
Collapse
Affiliation(s)
- Marco Zarbin
- Rutgers New Jersey Medical School, Newark, NJ 07103, USA.
| |
Collapse
|
43
|
Qu Z, Guan Y, Cui L, Song J, Gu J, Zhao H, Xu L, Lu L, Jin Y, Xu GT. Transplantation of rat embryonic stem cell-derived retinal progenitor cells preserves the retinal structure and function in rat retinal degeneration. Stem Cell Res Ther 2015; 6:219. [PMID: 26553210 PMCID: PMC4640237 DOI: 10.1186/s13287-015-0207-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Revised: 09/08/2015] [Accepted: 09/09/2015] [Indexed: 11/18/2022] Open
Abstract
INTRODUCTION Degenerative retinal diseases like age-related macular degeneration (AMD) are the leading cause of blindness. Cell transplantation showed promising therapeutic effect for such diseases, and embryonic stem cell (ESC) is one of the sources of such donor cells. Here, we aimed to generate retinal progenitor cells (RPCs) from rat ESCs (rESCs) and to test their therapeutic effects in rat model. METHODS The rESCs (DA8-16) were cultured in N2B27 medium with 2i, and differentiated to two types of RPCs following the SFEBq method with modifications. For rESC-RPC1, the cells were switched to adherent culture at D10, while for rESC-RPC2, the suspension culture was maintained to D14. Both RPCs were harvested at D16. Primary RPCs were obtained from P1 SD rats, and some of them were labeled with EGFP by infection with lentivirus. To generate Rax::EGFP knock-in rESC lines, TALENs were engineered to facilitate homologous recombination in rESCs, which were cotransfected with the targeting vector and TALEN vectors. The differentiated cells were analyzed with live image, immunofluorescence staining, flow cytometric analysis, gene expression microarray, etc. RCS rats were used to mimic the degeneration of retina and test the therapeutic effects of subretinally transplanted donor cells. The structure and function of retina were examined. RESULTS We established two protocols through which two types of rESC-derived RPCs were obtained and both contained committed retina lineage cells and some neural progenitor cells (NPCs). These rESC-derived RPCs survived in the host retinas of RCS rats and protected the retinal structure and function in early stage following the transplantation. However, the glia enriched rESC-RPC1 obtained through early and longer adherent culture only increased the b-wave amplitude at 4 weeks, while the longer suspension culture gave rise to evidently neuronal differentiation in rESC-RPC2 which significantly improved the visual function of RCS rats. CONCLUSIONS We have successfully differentiated rESCs to glia enriched RPCs and retinal neuron enriched RPCs in vitro. The retinal neuron enriched rESC-RPC2 protected the structure and function of retina in rats with genetic retinal degeneration and could be a candidate cell source for treating some degenerative retinal diseases in human trials.
Collapse
Affiliation(s)
- Zepeng Qu
- Laboratory of Molecular Developmental Biology, Shanghai Jiao Tong University School of Medicine, Room 208, Building 5, 280 South Chongqing Road, Shanghai, 200025, China.
| | - Yuan Guan
- Laboratory of Molecular Developmental Biology, Shanghai Jiao Tong University School of Medicine, Room 208, Building 5, 280 South Chongqing Road, Shanghai, 200025, China.
| | - Lu Cui
- Laboratory of Molecular Developmental Biology, Shanghai Jiao Tong University School of Medicine, Room 208, Building 5, 280 South Chongqing Road, Shanghai, 200025, China.
| | - Jian Song
- ShanghaiTech University School of Life Science and Technology, Shanghai, 201210, China.
| | - Junjie Gu
- Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences/Shanghai Jiao Tong University School of Medicine, Shanghai, 200031, China.
| | - Hanzhi Zhao
- Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences/Shanghai Jiao Tong University School of Medicine, Shanghai, 200031, China.
| | - Lei Xu
- Department of Regenerative Medicine, Stem Cell Research Center, and Institute for Nutritional Sciences, Tongji University School of Medicine, Shanghai, 200092, China.
| | - Lixia Lu
- Department of Ophthalmology of Shanghai Tenth People's Hospital, and Laboratory of Clinical Visual Science of Tongji Eye Institute, Tongji University School of Medicine, 1239 Siping Road, Medical Building, Room 521, Shanghai, 200092, China.
- Department of Regenerative Medicine, Stem Cell Research Center, and Institute for Nutritional Sciences, Tongji University School of Medicine, Shanghai, 200092, China.
| | - Ying Jin
- Laboratory of Molecular Developmental Biology, Shanghai Jiao Tong University School of Medicine, Room 208, Building 5, 280 South Chongqing Road, Shanghai, 200025, China.
- Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences/Shanghai Jiao Tong University School of Medicine, Shanghai, 200031, China.
- ShanghaiTech University School of Life Science and Technology, Shanghai, 201210, China.
| | - Guo-Tong Xu
- Department of Ophthalmology of Shanghai Tenth People's Hospital, and Laboratory of Clinical Visual Science of Tongji Eye Institute, Tongji University School of Medicine, 1239 Siping Road, Medical Building, Room 521, Shanghai, 200092, China.
- Department of Regenerative Medicine, Stem Cell Research Center, and Institute for Nutritional Sciences, Tongji University School of Medicine, Shanghai, 200092, China.
| |
Collapse
|
44
|
Pearson C, Martin K. Stem cell approaches to glaucoma: from aqueous outflow modulation to retinal neuroprotection. PROGRESS IN BRAIN RESEARCH 2015; 220:241-56. [PMID: 26497794 DOI: 10.1016/bs.pbr.2015.04.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Long-term pharmacological management of glaucoma currently relies on self-administered drugs to regulate intraocular pressure (IOP). A number of approaches using stem cells have recently shown promise as potential future treatment strategies complementary to IOP lowering. Several sources of endogenous stem cells have been identified in the eye, some of which may be able to repair the damaged trabecular meshwork and restore functional regulation of aqueous outflow. Neural and mesenchymal stem cells secrete growth factors which provide neuroprotective effects, reducing loss of retinal ganglion cells (RGCs) in animal models. In the future, stem cells may even replace RGCs to reform functional connections between the eye and the brain, although the complexity of such a repair task is formidable. With advances in biomaterial cell scaffolds and concurrent efforts in other neural systems, stem cell therapies are becoming a realistic option for treating multiple eye diseases, and despite ongoing challenges, there are reasons for optimism that stem cells may play a role in the treatment of human glaucoma in the future.
Collapse
Affiliation(s)
- Craig Pearson
- John van Geest Centre for Brain Repair, University of Cambridge, Cambridge, UK; Cambridge NIHR Biomedical Research Centre, Cambridge, UK; National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Keith Martin
- John van Geest Centre for Brain Repair, University of Cambridge, Cambridge, UK; Cambridge NIHR Biomedical Research Centre, Cambridge, UK; Wellcome Trust Medical Research Council Cambridge Stem Cell Institute, Cambridge, UK.
| |
Collapse
|
45
|
Tsai Y, Lu B, Bakondi B, Girman S, Sahabian A, Sareen D, Svendsen CN, Wang S. Human iPSC-Derived Neural Progenitors Preserve Vision in an AMD-Like Model. Stem Cells 2015; 33:2537-49. [PMID: 25869002 DOI: 10.1002/stem.2032] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 03/28/2015] [Indexed: 12/14/2022]
Abstract
Pluripotent stem cell-derived retinal pigment epithelial (RPE) cells are currently being tested for cell replacement in late-stage age-related macular degeneration (AMD). However, preserving vision at early-stages may also be possible. Here, we demonstrate that transplantation of neural progenitor cells (NPCs) derived from induced pluripotent stem cells (iNPCs) limits disease progression in the Royal College of Surgeons rat, a preclinical model of AMD. Grafted-iNPCs survived, remained undifferentiated, and distributed extensively in a laminar fashion in the subretinal space. Retinal pathology resulting from the accumulation of undigested photoreceptor outer segments (POS) was significantly reduced in iNPC-injected rats compared with controls. Phagosomes within grafted-iNPCs contained POS, suggesting that iNPCs had compensated for defective POS phagocytosis by host-RPE. The iNPC-treated eyes contained six to eight rows of photoreceptor nuclei that spanned up to 5 mm in length in transverse retinal sections, compared with only one row of photoreceptors in controls. iNPC treatment fully preserved visual acuity measured by optokinetic response. Electrophysiological recordings revealed that retina with the best iNPC-protected areas were 140-fold more sensitive to light stimulation than equivalent areas of contralateral eyes. The results described here support the therapeutic utility of iNPCs as autologous grafts for early-stage of AMD.
Collapse
Affiliation(s)
- Yuchun Tsai
- Department of Biomedical Sciences, Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Bin Lu
- Department of Biomedical Sciences, Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Benjamin Bakondi
- Department of Biomedical Sciences, Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Sergey Girman
- Department of Biomedical Sciences, Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Anais Sahabian
- Department of Biomedical Sciences, Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Dhruv Sareen
- Department of Biomedical Sciences, Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Clive N Svendsen
- Department of Biomedical Sciences, Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Shaomei Wang
- Department of Biomedical Sciences, Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, California, USA
| |
Collapse
|
46
|
Jankowiak W, Kruszewski K, Flachsbarth K, Skevas C, Richard G, Rüther K, Braulke T, Bartsch U. Sustained Neural Stem Cell-Based Intraocular Delivery of CNTF Attenuates Photoreceptor Loss in the nclf Mouse Model of Neuronal Ceroid Lipofuscinosis. PLoS One 2015; 10:e0127204. [PMID: 25992714 PMCID: PMC4439090 DOI: 10.1371/journal.pone.0127204] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 04/13/2015] [Indexed: 01/10/2023] Open
Abstract
A sustained intraocular administration of neurotrophic factors is among the strategies aimed at establishing treatments for currently untreatable degenerative retinal disorders. In the present study we have analyzed the neuroprotective effects of a continuous neural stem (NS) cell-based intraocular delivery of ciliary neurotrophic factor (CNTF) on photoreceptor cells in the nclf mouse, an animal model of the neurodegenerative lysosomal storage disorder variant late infantile neuronal ceroid lipofuscinosis (vLINCL). To this aim, we genetically modified adherently cultivated NS cells with a polycistronic lentiviral vector encoding a secretable variant of CNTF together with a Venus reporter gene (CNTF-NS cells). NS cells for control experiments (control-NS cells) were modified with a vector encoding the reporter gene tdTomato. Clonal CNTF-NS and control-NS cell lines were established using fluorescent activated cell sorting and intravitreally grafted into 14 days old nclf mice at the onset of retinal degeneration. The grafted cells preferentially differentiated into astrocytes that were attached to the posterior side of the lenses and the vitreal side of the retinas and stably expressed the transgenes for at least six weeks, the latest post-transplantation time point analyzed. Integration of donor cells into host retinas, ongoing proliferation of grafted cells or adverse effects of the donor cells on the morphology of the host eyes were not observed. Quantitative analyses of host retinas two, four and six weeks after cell transplantation revealed the presence of significantly more photoreceptor cells in eyes with grafted CNTF-NS cells than in eyes with grafted control-NS cells. This is the first demonstration that a continuous intraocular administration of a neurotrophic factor attenuates retinal degeneration in an animal model of neuronal ceroid lipofuscinosis.
Collapse
Affiliation(s)
- Wanda Jankowiak
- Department of Ophthalmology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Katharina Kruszewski
- Department of Ophthalmology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Kai Flachsbarth
- Department of Ophthalmology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Christos Skevas
- Department of Ophthalmology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Gisbert Richard
- Department of Ophthalmology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Klaus Rüther
- Department of Ophthalmology, Sankt Gertrauden-Krankenhaus, Berlin, Germany
| | - Thomas Braulke
- Department of Biochemistry, Children’s Hospital, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Udo Bartsch
- Department of Ophthalmology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- * E-mail:
| |
Collapse
|
47
|
Lu B, Lin Y, Tsai Y, Girman S, Adamus G, Jones MK, Shelley B, Svendsen CN, Wang S. A Subsequent Human Neural Progenitor Transplant into the Degenerate Retina Does Not Compromise Initial Graft Survival or Therapeutic Efficacy. Transl Vis Sci Technol 2015; 4:7. [PMID: 25694843 PMCID: PMC4324446 DOI: 10.1167/tvst.4.1.7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Accepted: 12/19/2014] [Indexed: 12/14/2022] Open
Abstract
PURPOSE Stem and progenitor cell transplantation provides a promising clinical application for treating degenerative retinal diseases, including age-related macular degeneration (AMD) and retinitis pigmentosa (RP). Our previous studies have shown that a single subretinal injection of human cortical-derived neural progenitor cells (hNPCctx) into cyclosporine-treated Royal College of Surgeons (RCS) rats preserved both photoreceptors and visual function. However, it is still unknown whether nonautologous progenitor cell readministration for sustained vision is efficacious and safe in terms of the initial graft initiating an immune response to a subsequent graft. METHODS A cell suspension containing 3×104 hNPCctx into one eye of cyclosporine-treated RCS rats at postnatal day 21 (P21), followed by a second transplantation at P95 into the previously untreated fellow eye. RESULTS hNPCctx delayed photoreceptor degeneration and preserved visual function, as measured by electroretinography (ERG), optokinetic response (OKR), and luminance threshold recordings (LTRs). Visual function and photoreceptors of the initially treated eye were still preserved 6 weeks after hNPCctx were injected into the second eye. Antibodies against T-cell markers showed that CD3, CD4, and CD8 T cells were not detected at P90 and P140 in most cases. No detectable level of anti-nestin antibody was found in serum by enzyme-linked immunosorbent assay (ELISA). CONCLUSIONS This xenograft study with cyclosporine-treated animals demonstrates that readministration of hNPCctx into the fellow eye did not induce anti-graft immune responses or lower therapeutic efficacy of hNPCctx in preserving vision. Thus, readministration of progenitor cells to sustain long-term efficacy may be an option for long-term therapies of retinal degeneration. TRANSLATIONAL RELEVANCE Redosing neural progenitors do not affect the efficacy of the initial grafts in protecting vision or induce unwanted immune responses.
Collapse
Affiliation(s)
- Bin Lu
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Yanhua Lin
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Yuchun Tsai
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Sergey Girman
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | | | - Melissa K. Jones
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Brandon Shelley
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Clive N. Svendsen
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Shaomei Wang
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| |
Collapse
|
48
|
Emre E, Yüksel N, Duruksu G, Pirhan D, Subaşi C, Erman G, Karaöz E. Neuroprotective effects of intravitreally transplanted adipose tissue and bone marrow-derived mesenchymal stem cells in an experimental ocular hypertension model. Cytotherapy 2015; 17:543-59. [PMID: 25618560 DOI: 10.1016/j.jcyt.2014.12.005] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 12/05/2014] [Accepted: 12/05/2014] [Indexed: 12/17/2022]
Abstract
BACKGROUND AIMS The purpose of this study was to investigate the neuroprotective effects of bone marrow bone marrow-derived and adipose tissue-derived mesenchymal stromal cells (MSCs) that were intravitreally transplanted in an experimental ocular hypertension (OHT) model. METHODS An OHT rat model was generated by means of intracameral injection of hyaluronic acid into the anterior chamber. MSCs labeled with green fluorescence protein were transplanted intravitreally 1 week after OHT induction. At the end of the second and fourth weeks, retinal ganglion cells were visualized with the use of a flat-mount retina method and were evaluated by means of immunofluorescence staining against green fluorescence protein, vimentin, CD105, and cytokines (interleukin [IL]-1Ra, prostaglandin E2 receptor, IL-6, transforming growth factor-β1, interferon-γ and tumor necrosis factor-α). RESULTS The retinal ganglion cell numbers per area were significantly improved in stem cell-treated OHT groups compared with that in the non-treated OHT group (P < 0.05). The results of immunohistochemical analyses indicated that a limited number of stem cells had integrated into the ganglion cell layer and the inner nuclear layer. The number of cells expressing proinflammatory cytokines (interferon-γ and tumor necrosis factor-α) decreased in the MSC-transferred group compared with that in the OHT group after 4 weeks (P < 0.01). On the other hand, IL-1Ra and prostaglandin E2 receptor expressions were increased in the rat bone marrow-derived MSC group but were more significant in the rat adipose tissue-derived MSC group (P < 0.01). CONCLUSIONS After intravitreal transplantation, MSCs showed a neuroprotective effect in the rat OHT model. Therefore, MSCs promise an alternative therapy approach for functional recovery in the treatment of glaucoma.
Collapse
Affiliation(s)
- Esra Emre
- Department of Ophthalmology, Çerkezköy State Hospital, Tekirdağ, Turkey.
| | - Nurşen Yüksel
- Department of Ophthalmology, School of Medicine, Kocaeli University, Kocaeli, Turkey
| | - Gökhan Duruksu
- Center for Stem Cell and Gene Therapies Research and Practice, Kocaeli University, Kocaeli, Turkey
| | - Dilara Pirhan
- Department of Ophthalmology, School of Medicine, Kocaeli University, Kocaeli, Turkey
| | - Cansu Subaşi
- Liv Hospital, Center for Regenerative Medicine and Stem Cell Research & Manufacturing (Liv MedCell) Istanbul, Turkey
| | - Gülay Erman
- Center for Stem Cell and Gene Therapies Research and Practice, Kocaeli University, Kocaeli, Turkey
| | - Erdal Karaöz
- Liv Hospital, Center for Regenerative Medicine and Stem Cell Research & Manufacturing (Liv MedCell) Istanbul, Turkey
| |
Collapse
|
49
|
Glial cell line-derived neurotrophic factor-secreting human neural progenitors show long-term survival, maturation into astrocytes, and no tumor formation following transplantation into the spinal cord of immunocompromised rats. Neuroreport 2014; 25:367-72. [PMID: 24284956 PMCID: PMC3969154 DOI: 10.1097/wnr.0000000000000092] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Human neural progenitor cells (hNPCs) derived from the fetal cortex can be expanded in vitro and genetically modified through lentiviral transduction to secrete growth factors shown to have a neurotrophic effect in animal models of neurological disease. hNPCs survive and mature following transplantation into the central nervous system of large and small animals including the rat model of amyotrophic lateral sclerosis. Here we report that hNPCs engineered to express glial cell line-derived neurotrophic factor (GDNF) survive long-term (7.5 months) following transplantation into the spinal cord of athymic nude rats and continue to secrete GDNF. Cell proliferation declined while the number of astrocytes increased, suggesting final maturation of the cells over time in vivo. Together these data show that GDNF-producing hNPCs may be useful as a source of cells for long-term delivery of both astrocytes and GDNF to the damaged central nervous system.
Collapse
|
50
|
Wiley LA, Burnight ER, Mullins RF, Stone EM, Tucker BA. Stem cells as tools for studying the genetics of inherited retinal degenerations. Cold Spring Harb Perspect Med 2014; 5:a017160. [PMID: 25502747 DOI: 10.1101/cshperspect.a017160] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The ability to provide early clinical intervention for inherited disorders is heavily dependent on knowledge of a patient's disease-causing mutations and the resultant pathophysiologic mechanism(s). Without knowing a patient's disease-causing gene, and how gene mutations alter the health and functionality of affected cells, it would be difficult to develop and deliver patient-specific molecular or small molecule therapies. Many believe that the field of stem cell biology holds the keys to the future development of disease-, patient-, and cell-specific therapies. In the case of the eye, which is susceptible to an extremely common late-onset degenerative disease known as age-related macular degeneration, stem cell-based therapies could increase the quality of life for millions of patients worldwide. Furthermore, autologous, patient-specific induced pluripotent stem cells could be a viable source to treat rare Mendelian retinal degenerative diseases such as retinitis pigmentosa, Stargardt disease, and Best disease, to name a few.
Collapse
Affiliation(s)
- Luke A Wiley
- Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, Iowa 52242
| | - Erin R Burnight
- Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, Iowa 52242
| | - Robert F Mullins
- Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, Iowa 52242
| | - Edwin M Stone
- Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, Iowa 52242 Howard Hughes Medical Institute, University of Iowa, Iowa City, Iowa 52242
| | - Budd A Tucker
- Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, Iowa 52242
| |
Collapse
|